Theoretische Chemie - Klüner

Hochschulbibliographie

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Publikationen der Arbeitsgruppe

  • M. Becker, T. Klüner, und M. Wark, "Formation of hybrid ABX3 perovskite compounds for solar cell application: first-principles calculations of effective ionic radii and determination of tolerance factors," Dalton Trans., vol. 46, pp. 3500-3509, 2017.
    @Article{Becker2017,
      author ="Becker, Markus and Klüner, Thorsten and Wark, Michael", title ="Formation of hybrid ABX3 perovskite compounds for solar cell application: first-principles calculations of effective ionic radii and determination of tolerance factors", journal ="Dalton Trans.", year ="2017", volume ="46", issue ="11", pages ="3500-3509", publisher ="The Royal Society of Chemistry", doi ="10.1039/C6DT04796C", url ="http://dx.doi.org/10.1039/C6DT04796C", abstract ="The development of hybrid organic-inorganic perovskite solar cells is one of the most rapidly growing fields in the photovoltaic community and is on its way to challenge polycrystalline silicon and thin film technologies. High power conversion efficiencies can be achieved by simple processing with low cost. However{,} due to the limited long-term stability and environmental toxicity of lead in the prototypic CH3NH3PbI3{,} there is a need to find alternative ABX3 constitutional combinations in order to promote commercialization. The Goldschmidt tolerance factor and the octahedral factor were found to be necessary geometrical concepts to evaluate which perovskite compounds can be formed. It was figured out that the main challenge lies in estimating an effective ionic radius for the molecular cation. We calculated tolerance factors and octahedral factors for 486 ABX3 monoammonium-metal-halide combinations{,} where the steric size of the molecular cation in the A-position was estimated concerning the total charge density. A thorough inquiry about existing mixed organic-inorganic perovskites was undertaken. Our results are in excellent agreement with the reported hybrid compounds and indicate the potential existence of 106 ABX3 combinations hitherto not discussed in the literature{,} giving hints for more intense research on prospective individual candidates."}
  • C. Lasar und T. Klüner, "Explicitly Correlated Orbital Optimized Contracted Pair Correlation Methods: A Short Overview," J. Phys. Chem. A, vol. 121, iss. 24, pp. 4707-4711, 2017.
    @article{Lasar2017,
      author = {Lasar, Christian and Klüner, Thorsten},
      title = {Explicitly Correlated Orbital Optimized Contracted Pair Correlation Methods: A Short Overview},
      journal = {J. Phys. Chem. A},
      volume = {121},
      number = {24},
      pages = {4707-4711},
      year = {2017},
      doi = {10.1021/acs.jpca.7b03960},
      note ={PMID: 28570077},
      URL = { http://dx.doi.org/10.1021/acs.jpca.7b03960 },
      eprint = { http://dx.doi.org/10.1021/acs.jpca.7b03960 } }
  • T. Oswald, T. Gelert, C. Lasar, M. Schmidtmann, T. Klüner, und R. Beckhaus, "Formation of Binuclear Zigzag Hexapentaene Titanium Complexes via a Titanacumulene [Ti=C=C=CH2] Intermediate," Angew. Chem. Int. Ed., vol. 56, iss. 40, pp. 12297-12301, 2017.
    @article {Oswald2017,
      author = {Oswald, Tim and Gelert, Tina and Lasar, Christian and Schmidtmann, Marc and Klüner, Thorsten and Beckhaus, Rüdiger},
      title = {Formation of Binuclear Zigzag Hexapentaene Titanium Complexes via a Titanacumulene [Ti=C=C=CH2] Intermediate},
      journal = {Angew. Chem. Int. Ed.},
      volume = {56},
      number = {40},
      issn = {1521-3773},
      url = {http://dx.doi.org/10.1002/anie.201706674},
      doi = {10.1002/anie.201706674},
      pages = {12297--12301},
      keywords = {C−H activation, hexapentaene, pentafulvene, titanabutatriene, titanium},
      year = {2017},
      }
  • A. G. Thome, N. Ayral, H. Toufar, T. Klüner, und F. Roessner, "Dehydration of 2,3-Butanediol: A Catalytical and Theoretical Approach," Catal. Lett., vol. 147, iss. 5, pp. 1271-1277, 2017.
    @Article{Thome2017,
      author="Thome, Andreas Georg and Ayral, Nils and Toufar, Helge and Kl{\"u}ner, Thorsten and Roessner, Frank", title="Dehydration of 2,3-Butanediol: A Catalytical and Theoretical Approach", journal="Catal. Lett.", year="2017", month="May", day="01", volume="147", number="5", pages="1271--1277", abstract="The catalytic behavior of several acidic and alkaline solids was investigated in the heterogeneous dehydration of 2,3-butanediol in the temperature range of 350--800{\thinspace}{\textdegree}C. At low temperatures butanone is the main product for all used catalysts. Its yield decreases with increasing temperatures. The formation of 1,3-butadiene was observed over the whole temperature range. Its maximum formation around 700{\thinspace}{\textdegree}C was explained in term of non-catalytic thermal dehydration. DFT calculations of the dehydration steps were made to explain the results. It was shown, that a hydride shift directs the reaction towards the formation of butanone.", issn="1572-879X", doi="10.1007/s10562-017-2027-3", url="https://doi.org/10.1007/s10562-017-2027-3" }
  • J. Mitschker und T. Klüner, "Photodissociation of water on rutile (110): A wave packet approach based on first principles," J. Theor. Comput. Chem., vol. 15, iss. 02, p. 1650013, 2016.
    @Article{Mitschker2016, Title = {Photodissociation of water on rutile (110): A wave packet approach based on first principles},
      Author = {Mitschker, Jan and Klüner, Thorsten},
      Journal = {J. Theor. Comput. Chem.},
      Pages = {1650013},
      Volume = {15},
      Year = {2016},
      Number = {02},
      Doi = {10.1142/S0219633616500139},
      Url = {http://dx.doi.org/10.1142/S0219633616500139} }
  • J. Bruns, D. van Gerven, T. Klüner, und M. S. Wickleder, "Palladium(IV) in an Oxoanionic Environment: The XeF2 Assisted Synthesis of [Pd(S2O7)3]2−," Angew. Chem. Int. Ed., vol. 55, iss. 28, pp. 8121-8124, 2016.
    @Article {Bruns2016,
      author = {Bruns, Jörn and van Gerven, David and Klüner, Thorsten and Wickleder, Mathias S.},
      title = {Palladium(IV) in an Oxoanionic Environment: The XeF2 Assisted Synthesis of [Pd(S2O7)3]2−},
      journal = {Angew. Chem. Int. Ed.},
      volume = {55},
      number = {28},
      issn = {1521-3773},
      url = {http://dx.doi.org/10.1002/anie.201601767},
      doi = {10.1002/anie.201601767},
      pages = {8121--8124},
      keywords = {density functional theory, disulfate, palladium, structure elucidation, vibrational spectroscopy},
      year = {2016},
      }
  • L. V. Schindler, T. Klüner, und M. S. Wickleder, "Towards Polysulfuric Acids: The Hydrogentrisulfate Anion [HS3O10]− in A[HS3O10] (A=Na, K, Rb)," Chemistry – A European Journal, vol. 22, iss. 39, pp. 13865-13870, 2016.
    @Article {Schindler2016a,
      author = {Schindler, Lisa Verena and Klüner, Thorsten and Wickleder, Mathias S.},
      title = {Towards Polysulfuric Acids: The Hydrogentrisulfate Anion [HS3O10]− in A[HS3O10] (A=Na, K, Rb)},
      journal = {Chemistry – A European Journal},
      volume = {22},
      number = {39},
      issn = {1521-3765},
      url = {http://dx.doi.org/10.1002/chem.201602176},
      doi = {10.1002/chem.201602176},
      pages = {13865--13870},
      keywords = {crystal structures, hydrogen bonds, hydrogentrisulfate, polysulfuric acids, quantum mechanical calculations},
      year = {2016},
      }
  • L. V. Schindler, A. Becker, M. Wieckhusen, T. Klüner, und M. S. Wickleder, "Polysulfates [SnO3n+1]2−: With the [S6O19]2− Anion, has the End been Reached?," Angew. Chem. Int. Ed., vol. 55, iss. 52, pp. 16165-16167, 2016.
    @Article {Schindler2016b,
      author = {Schindler, Lisa Verena and Becker, Anna and Wieckhusen, Maria and Klüner, Thorsten and Wickleder, Mathias S.},
      title = {Polysulfates [SnO3n+1]2−: With the [S6O19]2− Anion, has the End been Reached?},
      journal = {Angew. Chem. Int. Ed.},
      volume = {55},
      number = {52},
      issn = {1521-3773},
      url = {http://dx.doi.org/10.1002/anie.201607629},
      doi = {10.1002/anie.201607629},
      pages = {16165--16167},
      keywords = {polysulfates, solid-state chemistry, structural chemistry},
      year = {2016},
      }
  • [incollection] bibtex | Dokument aufrufen Dokument aufrufen
    J. Mitschker und T. Klüner, "Adsorption and Electronic Excitation of Water on TiO2 (110): Calculation of High-Dimensional Potential Energy Surfaces," in High Performance Computing in Science and Engineering ‘14, Nagel, W. E., Kröner, D. H., und Resch, M. M., Eds., Springer International Publishing, 2015, pp. 191-203.
    @InCollection{Mitschker2015, Title = {Adsorption and Electronic Excitation of Water on TiO2 (110): Calculation of High-Dimensional Potential Energy Surfaces},
      Author = {Mitschker, Jan and Klüner, Thorsten},
      Booktitle = {High Performance Computing in Science and Engineering ‘14},
      Publisher = {Springer International Publishing},
      Year = {2015},
      Editor = {Nagel, Wolfgang E. and Kröner, Dietmar H. and Resch, Michael M.},
      Pages = {191-203},
      Url = {http://dx.doi.org/10.1007/978-3-319-10810-0_14} }
  • I. Brand, F. Habecker, M. Ahlers, und T. Klüner, "Structure of collagen adsorbed on a model implant surface resolved by polarization modulation infrared reflection-absorption spectroscopy," Spectrochimica Acta Part A-molecular and Biomolecular Spectroscopy, vol. 138, pp. 216-224, 2015.
    @Article{Brand2015, Title = {Structure of collagen adsorbed on a model implant surface resolved by polarization modulation infrared reflection-absorption spectroscopy},
      Author = {Brand, Izabella and Habecker, Florian and Ahlers, Michael and Klüner, Thorsten},
      Journal = {Spectrochimica Acta Part A-molecular and Biomolecular Spectroscopy},
      Pages = {216--224},
      Volume = {138},
      Year = {2015},
      Month = mar, Abstract = {The polarization modulation infrared reflection-absorption spectra of collagen adsorbed on a titania surface and quantum chemical calculations are used to describe components of the amide I mode to the protein structure at a sub-molecular level. In this study, imino acid rich and poor fragments, representing the entire collagen molecule, are taken into account. The amide I mode of the collagen triple helix is composed of three absorption bands which involve: (i) (similar to 1690 cm(-1)) the C=O stretching modes at unhydrated groups, (ii) (1655-1673 cm(-1)) the C=O stretching at carbonyl groups at imino acids and glycine forming intramolecular hydrogen bonds with H atoms at both NH2 and, unusual for proteins, CH2 groups at glycine at a neighbouring chain and (iii) (similar to 1640 cm(-1)) the C=O stretching at carbonyl groups forming hydrogen bonds between two, often charged, amino acids as well as hydrogen bonds to water along the entire helix. The IR spectrum of films prepared from diluted solutions (c < 50 mu g ml(-1)) corresponds to solution spectra indicating that native collagen molecules interact with water adsorbed on the titania surface. In films prepared from solutions (c >= 50 mu g ml(-1)) collagen multilayers are formed. The amide I mode is blueshifted by 18 cm(-1), indicating that intramolecular hydrogen bonds at imino acid rich fragments are weakened. Simultaneous red-shift of the amide A mode implies that the strength of hydrogen bonds at the imino acid poor fragments increases. Theoretically predicted distortion of the collagen structure upon adsorption on the titania surface is experimentally confirmed. (C) 2014 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.saa.2014.11.031} }
  • J. Mitschker und T. Klüner, "Photodesorption of water from rutile(110): ab initio calculation of five-dimensional potential energy surfaces of ground and excited electronic states and wave packet studies," Phys. Chem. Chem. Phys., vol. 17, iss. 1, pp. 268-275, 2015.
    @Article{Mitschker2015a, Title = {Photodesorption of water from rutile(110): ab initio calculation of five-dimensional potential energy surfaces of ground and excited electronic states and wave packet studies},
      Author = {Mitschker, Jan and Klüner, Thorsten},
      Journal = {Phys. Chem. Chem. Phys.},
      Pages = {268--275},
      Volume = {17},
      Year = {2015},
      Number = {1},
      Abstract = {In this paper, we report on our results concerning the interaction of water with titanium dioxide in its rutile modification. The (110) surface is modelled by an embedded Ti9O18Mg714+ cluster. We present up to five-dimensional potential energy surfaces for the water molecule on this surface and include the dissociation of one hydrogen atom. The electronic ground state as well as one electronically excited state is included. To deal with the multi-configurational character of the wave function, we use the complete active space self-consistent field (CASSCF) approach. The resulting potential energy surfaces are fitted by means of an artificial neural network. As a first example of quantum dynamical studies based on our potential surfaces, we present results on the photodesorption of water from rutile(110).},
      Url = {http://dx.doi.org/10.1039/c4cp04593a} }
  • L. V. Moskaleva, T. Weiss, T. Klüner, und M. Bäumer, "Chemisorbed Oxygen on the Au(321) Surface Alloyed with Silver: A First-Principles Investigation," J. Phys. Chem. C, vol. 119, iss. 17, pp. 9215-9226, 2015.
    @Article{Moskaleva2015, Title = {Chemisorbed Oxygen on the Au(321) Surface Alloyed with Silver: A First-Principles Investigation},
      Author = {Moskaleva, Lyudmila V. and Weiss, Theodor and Klüner, Thorsten and Bäumer, Marcus},
      Journal = {J. Phys. Chem. C},
      Pages = {9215--9226},
      Volume = {119},
      Year = {2015},
      Month = apr, Number = {17},
      Abstract = {The adsorption of oxygen on kinked Au(321) slabs is investigated theoretically on the basis of density functional theory. On-surface, subsurface, and surface-oxide forms of O are analyzed and compared on pure gold and on the surfaces containing silver atoms. At low O coverage (0.1 ML) subsurface O species are shown to be unstable both thermodynamically and kinetically due to a low barrier for conversion to stronger bound on-surface chemisorbed oxygen. The presence of Ag in the near-surface region was shown to increase the binding strength of on-surface as well as subsurface O, but the activation barrier for releasing subsurface O to the surface remains essentially unaffected by the presence of Ag. At oxygen coverage 0.2 ML or higher, the most stable surface arrangements of Oatoms are chain-like structures consisting of linear -O-Au-O- fragments. Subsurface O atoms being a part of such chains are significantly stabilized. We examine phase transitions between the clean surface and possible stable oxidized surface structures as a function of temperature and O-2 partial pressure. Ag atoms replacing Au on the Au(321) surface are shown to stabilize the O-covered surface with respect to the clean surface. Pre-existent chemisorbed atomic oxygen is predicted to facilitate the dissociation of molecular oxygen on the pure and alloyed gold surfaces.},
      Url = {http://dx.doi.org/10.1021/jp511884k} }
  • J. Bruns, S. Krüger, M. Adlung, C. Wickleder, O. Niehaus, R. Pöttgen, T. Klüner, J. Kräuter, und M. S. Wickleder, "A Highly Triflated Rare-Earth Ion in [Eu(O3SCF3)8]5−," Chemistry – A European Journal, vol. 21, iss. 35, pp. 12389-12395, 2015.
    @Article{Bruns2015a, Title = {A Highly Triflated Rare-Earth Ion in [Eu(O3SCF3)8]5−},
      Author = {Bruns, Jörn and Krüger, Sascha and Adlung, Matthias and Wickleder, Claudia and Niehaus, Oliver and Pöttgen, Rainer and Klüner, Thorsten and Kräuter, Jessica and Wickleder, Mathias S.},
      Journal = {Chemistry – A European Journal},
      Pages = {12389--12395},
      Volume = {21},
      Year = {2015},
      Number = {35},
      Doi = {10.1002/chem.201501941},
      ISSN = {1521-3765},
      Keywords = {europium, luminescence, rare earths, thermal decomposition, vibrational spectroscopy},
      Publisher = {WILEY-VCH Verlag},
      Url = {http://dx.doi.org/10.1002/chem.201501941} }
  • B. Schickmous, T. Klüner, und J. Christoffers, "Synthesis of Annulated and Spirocyclic Butenolide Derivatives by Condensation of Malonates with Cyclic $\alpha$-Hydroxy $\beta$-Dicarbonyl Compounds.," Synlett, vol. 26, iss. 10, pp. 1357-1360, 2015.
    @Article{Schickmous2015, Title = {Synthesis of Annulated and Spirocyclic Butenolide Derivatives by Condensation of Malonates with Cyclic $\alpha$-Hydroxy $\beta$-Dicarbonyl Compounds.},
      Author = {Schickmous, Barhiem and Klüner, Thorsten and Christoffers, Jens.},
      Journal = {Synlett},
      Pages = {1357--1360},
      Volume = {26},
      Year = {2015},
      Number = {10},
      Abstract = {Cyclocondensation of alicyclic and heterocyclic α-hydroxy β-dicarbonyl compds. with di-Me malonate gives bicyclic butenolide derivs. The reaction sequence is catalyzed by 4-(N,N-dimethylamino)pyridine and consists of two processes: Knövenagel condensation followed by transesterification. Depending on the chem. nature of the β-dicarbonyl moiety (oxoester, diketone or α-acetyl lactone or lactam), products with either annulated or spirocyclic constitution were obtained. [on SciFinder(R)]},
      Doi = {10.1002/chem.201501941},
      ISSN = {0936-5214},
      Publisher = {Georg Thieme Verlag},
      Url = {http://dx.doi.org/10.1002/chem.201501941} }
  • J. Bruns, T. Klüner, und M. S. Wickleder, "Oxoanionic Noble Metal Compounds from Fuming Nitric Acid: The Palladium Examples Pd(NO3)(2) and Pd(CH3SO3)(2)," Chem. Eur. J., vol. 21, iss. 3, pp. 1294-1301, 2015.
    @Article{Bruns2015, Title = {Oxoanionic Noble Metal Compounds from Fuming Nitric Acid: The Palladium Examples Pd(NO3)(2) and Pd(CH3SO3)(2)},
      Author = {Bruns, Jörn and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Chem. Eur. J.},
      Pages = {1294--1301},
      Volume = {21},
      Year = {2015},
      Month = jan, Number = {3},
      Abstract = {The oxidation of elemental palladium at 100 degrees C in a mixture of fuming nitric acid and a pyridine-SO3 complex leads to the anhydrous nitrate Pd(NO3)(2) (monoclinic, P2(1)/n, Z=2, a=469.12(3) pm, b=593.89(3) pm, c=805.72(4) pm, =105.989(3)degrees, V=215.79(2)angstrom(3)). The Pd2+ ions are in square-planar coordination with four monodentate nitrate groups which are connected to further palladium atoms, leading to a layer structure. The reaction of elemental palladium with a mixture of fuming nitric acid and methanesulfonic acid at 120 degrees C leads to single crystals of Pd(CH3SO3)(2) (monoclinic, P2(1)/n, Z=2, a=480.44(1) pm, b=1085.53(3) pm, c=739.78(2) pm, =102.785(1)degrees, V=376.254(17)angstrom(3)). Also in this structure the Pd2+ ions are in square-planar coordination with four monodentate anions; however, the connection to adjacent palladium atoms leads to a chain-type structure. The thermal decomposition of the compounds has been investigated by means of DSC/TG measurements. Furthermore, IR and Raman spectra have been recorded, and an assignment of the observed vibrational frequencies has been carried out based on theoretical investigations.},
      Url = {http://dx.doi.org/10.1002/chem.201405355} }
  • J. Bruns, T. Klüner, und M. S. Wickleder, "Ba$_2$[Pd(HS$_2$O$_7$)$_2$(S$_3$O$_10$)$_2$]: A Heteroleptic Polysulfatopalladate.," Chem. Asian J., vol. 9, iss. 6, pp. 1594-1600, 2014.
    @Article{Bruns2014a, Title = {Ba$_2$[Pd(HS$_2$O$_7$)$_2$(S$_3$O$_10$)$_2$]: A Heteroleptic Polysulfatopalladate.},
      Author = {Bruns, Jörn and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Chem. Asian J.},
      Pages = {1594--1600},
      Volume = {9},
      Year = {2014},
      Number = {6},
      Abstract = {The oxidn. of elemental palladium with oleum (65% SO3) in the presence of barium carbonate in torch-sealed glass ampuls at 180° leads to yellow single crystals of the heteroleptic palladate Ba2[Pd(HS2O7)2(S3O10)2] (1) (triclinic, Pbar1; Z = 1; a = 884.18(3), b 927.68(3), c 938.77(4) pm; α 60.473(1), β 80.266(2), γ 87.746(2)°). The crystal structure shows the Pd2+ ions in a square-planar coordination of oxygen atoms of two hydrogendisulfate and of two trisulfate anions. The compd. is the first example of the rarely seen S3O102- and HS2O7- anions acting as ligands in a complex anion and, moreover, the first heteroleptic polysulfatometalate known so far. The complex formation leads to a stabilization of the trisulfate anion relative to its uncoordinated congener. Ba2[Pd(HS2O7)2(S3O10)2] (1) was further characterized by vibrational spectroscopy and quantum chem. calcns. Thermal analyses by thermogravimetric/DTA (TG/DTA) measurements show that the compd. decomps. to yield elemental palladium and BaSO4. [on SciFinder(R)]},
      Url = {http://dx.doi.org/10.1002/asia.201402067} }
  • H. Spieker und T. Klüner, "Photoinduced desorption of CO from rutile TiO$_2$(110): elucidation of a new desorption mechanism using first principles," Phys. Chem. Chem. Phys., vol. 16, iss. 35, pp. 18743-18748, 2014.
    @Article{Spieker2014, Title = {Photoinduced desorption of CO from rutile TiO$_2$(110): elucidation of a new desorption mechanism using first principles},
      Author = {Spieker, Hendrik and Klüner, Thorsten},
      Journal = {Phys. Chem. Chem. Phys.},
      Pages = {18743--18748},
      Volume = {16},
      Year = {2014},
      Number = {35},
      Abstract = {Due to its high photocatalytic activity, TiO2 is of eminent interest for a manifold of applications ranging from surface catalysis up to solar energy conversion. However, the fundamental mechanisms of the underlying surface photochemistry are by no means understood. Focussing on this drawback, laser-induced photodesorption of CO on an ideal rutile TiO2(110) surface is studied using first principles in terms of a model system. This paper presents both quantum chemical as well as quantum dynamical results, taking into account the desorption coordinate Z, the polar angle theta, and the azimuth angle phi of the adsorbate. Detailed insight into the fundamental mechanisms of the photodesorption process in this model system is obtained, and a new desorption scenario is elucidated.},
      Url = {http://dx.doi.org/10.1039/c4cp02917h} }
  • E. Asplund und T. Klüner, "Quantum dynamical study of femtosecond photodesorption of CO from TiO$_2$(110)," J. Chem. Phys., vol. 141, iss. 8, p. 084715, 2014.
    @Article{Asplund2014, Title = {Quantum dynamical study of femtosecond photodesorption of CO from TiO$_2$(110)},
      Author = {Asplund, Erik and Klüner, Thorsten},
      Journal = {J. Chem. Phys.},
      Pages = {084715},
      Volume = {141},
      Year = {2014},
      Month = aug, Number = {8},
      Abstract = {The photodesorption of CO from TiO2(110) by femtosecond pulses is investigated with the Surrogate Hamiltonian approach. The aim of the study is to resolve the relaxation mechanism and forecast the lifetime of the exited state based on a microscopic description of the excitation and relaxation processes. The parameters characterizing the system are obtained from ab initio and Density Functional Theory-calculations with one parameter estimated from physical considerations and convergence studies. Two electronic states are considered and the relaxation is assumed to be due to the interaction of the excited adsorbate with electron hole pairs in the surface. Desorption probabilities and velocity distributions of the desorbing molecules are calculated and an exited state lifetime is predicted. Throughout this paper atomic units, i.e., (h) over bar = m(e) = e = a(0) = 1, have been used unless otherwise stated. (C) 2014 AIP Publishing LLC.},
      Url = {http://dx.doi.org/10.1063/1.4893528} }
  • J. Bruns, T. Klüner, und M. S. Wickleder, "Oxidizing Elemental Platinum with Oleum under Harsh Conditions: The Unique Tris(disulfato)platinate(IV) [Pt(S$_2$O$_7$)($_3$)]^2- Anion," Chem. Eur. J., vol. 20, iss. 24, pp. 7222-7227, 2014.
    @Article{Bruns2014, Title = {Oxidizing Elemental Platinum with Oleum under Harsh Conditions: The Unique Tris(disulfato)platinate(IV) [Pt(S$_2$O$_7$)($_3$)]^{2-} Anion},
      Author = {Bruns, Jörn and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Chem. Eur. J.},
      Pages = {7222--7227},
      Volume = {20},
      Year = {2014},
      Month = jun, Number = {24},
      Abstract = {For the first time, direct oxidation of elemental platinum by a mineral acid to its tetravalent state was observed in course of the reaction of platinum with oleum (65% SO3) in the presence of barium carbonate. The reaction has been carried out in torch-sealed glass ampoules at 160 degrees C and gave yellow single crystals of Ba[Pt(S2O7)(3)]-(H2SO4)(0.5)(H2S2O7)(0.5) (triclinic, P (1) over bar, Z = 2, a = 992.05(2), b = 1069.07(3), c = 1114.22(3) pm, alpha = 69.49(7), beta = 72.96(2), gamma = 72.93(1)degrees, V = 1033.95(5) angstrom(3)). The structure of Ba[Pt-(S2O7)(3)](H2SO4)(0.5)(H2S2O7)(0.5) exhibits the unique tris-(disulfato)-platinate anion [Pt(S2O7)(3)](2-) with three chelating disulfate groups coordinated to the platinum atom. Charge balance is achieved by the Ba2+ ions, which are coordinated by (S2O7)(2-) groups from the platinate complex and by disordered sulfuric acids and disulfuric acid molecules. Thermal decomposition of the bulk material revealed elemental platinum and barium sulfate as decomposition residual.},
      Url = {http://dx.doi.org/10.1002/chem.201402086} }
  • J. Bruns, T. Klüner, und M. S. Wickleder, "Bis(tetrasulfato)palladate, [Pd(S$_4$O$_13$)$_2$]^2-," Angew. Chem., Int. Ed., vol. 52, iss. 9, pp. 2590-2592, 2013.
    @Article{Bruns2013, Title = {Bis(tetrasulfato)palladate, [Pd(S$_4$O$_13$)$_2$]^{2-}},
      Author = {Bruns, Jörn and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Angew. Chem., Int. Ed.},
      Pages = {2590--2592},
      Volume = {52},
      Year = {2013},
      Number = {9},
      Url = {http://dx.doi.org/10.1002/anie.201209346} }
  • M. Arndt, S. Murali, und T. Klüner, "Interaction of NO with the TiO$_2$(110) surface: A quantum chemical study," Chem. Phys. Lett., vol. 556, pp. 98-101, 2013.
    @Article{Arndt2013, Title = {Interaction of NO with the TiO$_2$(110) surface: A quantum chemical study},
      Author = {Arndt, Marie and Murali, Sukumaran and Klüner, Thorsten},
      Journal = {Chem. Phys. Lett.},
      Pages = {98--101},
      Volume = {556},
      Year = {2013},
      Month = jan, Abstract = {The adsorption of NO on the rutile (TiO2(110)) surface has been investigated by restricted open shell Hartree-Fock (ROHF) and Moller-Plesset second order perturbation (ROMP2) theory. To mimic the TiO2 (110) surface, a Ti9O18Mg714+-cluster embedded in a field of point charges has been employed. The preferred orientation of NO on TiO2 (110) has been discussed in terms of 2D potential energy surfaces (PES) and a molecular orbital perspective. Adsorption energies of NO molecules in different electronic states were calculated by varying the distance coordinate and the polar angle. Our results reveal that a tilted orientation of the NO molecule on the TiO2 (110) surface is energetically preferred. (C) 2012 Elsevier B. V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.cplett.2012.11.057} }
  • E. Asplund und T. Klüner, "A Surrogate Hamiltonian study of femtosecond photodesorption of CO from NiO(100)," Mol. Phys., vol. 111, iss. 16-17, pp. 2377-2386, 2013.
    @Article{Asplund2013, Title = {A Surrogate Hamiltonian study of femtosecond photodesorption of CO from NiO(100)},
      Author = {Asplund, Erik and Klüner, Thorsten},
      Journal = {Mol. Phys.},
      Pages = {2377--2386},
      Volume = {111},
      Year = {2013},
      Month = sep, Number = {16-17},
      Abstract = {In this paper, the Surrogate Hamiltonian approach is employed in order to study electronic relaxation in femtosecond laser-induced desorption experiments of CO from NiO(100). The study is based on ab initio calculations and a microscopic description of the NiO(100)-surface and the relaxation mechanism developed by Koch etal. The relaxation mechanism is assumed to be of dipole-dipole interaction nature, where the transition dipole moment of the adsorbate interacts with surface electron-hole pairs. In the Surrogate Hamiltonian approach the electron-hole pairs are treated as two-level systems and are described by excitation energy and a dipole charge. The Surrogate Hamiltonian parameters and potential energy surfaces used are obtained from ab initio calculations. The desorption probability and the velocity distributions of the desorbing molecules are calculated and an excited state lifetime is predicted. Throughout this paper atomic units, i.e. ? = m(e) = e = a(0) = 1, have been used unless otherwise stated.},
      Url = {http://dx.doi.org/10.1080/00268976.2013.813589} }
  • M. Mehring und T. Klüner, "Calculation of two-dimensional potential energy surfaces of CO on a rutile(110) surface: ground and excited states," Mol. Phys., vol. 111, iss. 9-11, pp. 1612-1621, 2013.
    @Article{Mehring2013, Title = {Calculation of two-dimensional potential energy surfaces of CO on a rutile(110) surface: ground and excited states},
      Author = {Mehring, Matthias and Klüner, Thorsten},
      Journal = {Mol. Phys.},
      Pages = {1612--1621},
      Volume = {111},
      Year = {2013},
      Month = jul, Number = {9-11},
      Abstract = {Being one of the most important catalytically active metal oxide surfaces, the aim of this study was the description of the laser-induced photodesorption of the CO adsorbate from a TiO2(110) surface. As a first step, this paper presents two-dimensional potential energy surfaces of a CO molecule on a rutile TiO2(110) surface. Focussing on the desorption mechanism taking place in this adsorbate-substrate system, the quantum chemical and quantum dynamical calculations regarding the desorption coordinate Z and the polar angle allowed a first insight into the mechanistic processes in the CO-TiO2(110) system which are relevant for laser-induced photodesorption. For the electronic ground state X(1)A(1) the adsorption minimum was found for the polar angle = 0 degrees, which corresponds to a linear coordination of the CO adsorbate with the carbon atom down to the substrate surface. This is in contrast to the electronically excited state A(3)B(2), where the adsorption minimum was found for the polar angle = 180 degrees, which describes a linear coordination with the oxygen atom of the CO molecule on top of the rutile TiO2(110) surface. Moreover, this paper shows exemplary quantum dynamical calculations which simulate the laser-induced photodesorption as a first step to understand the desorption process in detail. Hence, higher dimensional calculations regarding more than 2 degrees of freedom of the CO molecule on the substrate surface are needed to get a complete description of this complex adsorbate-substrate system.},
      Url = {http://dx.doi.org/10.1080/00268976.2013.780106} }
  • W. Yim und T. Klüner, "Substrate Mediated Short- and Long-Range Adsorption Patterns of CO on Ag(110)," Phys. Rev. Lett., vol. 110, iss. 19, p. 196101, 2013.
    @Article{Yim2013, Title = {Substrate Mediated Short- and Long-Range Adsorption Patterns of CO on Ag(110)},
      Author = {Yim, Wai-Leung and Klüner, Thorsten},
      Journal = {Phys. Rev. Lett.},
      Pages = {196101},
      Volume = {110},
      Year = {2013},
      Month = may, Number = {19},
      Abstract = {The adsorption of CO on Ag(110) was recently explained using substrate mediated intermolecular interactions, but the underlying mechanism remains unclear. This study investigates both short- and long-range relaxation patterns for CO adsorption on Ag(110) surfaces and suggests that the relaxation mode can be explained by the interaction of heavy electrons on metal substrates in electron momentum space. The long-range relaxation mode for CO on Ag(110) involved a (6 x 6) commensurate phase, whereas the short-range relaxation involved an alleviation of Fermi surface nesting along the < 1 (1) over bar0 > direction of the Ag(110) substrate. The symmetry broken ground state structure at high CO coverage from this work is consistent with the interpretation of available experimental data at low temperature.},
      Url = {http://dx.doi.org/10.1103/PhysRevLett.110.196101} }
  • C. Logemann, T. Klüner, und M. S. Wickleder, "The Tetrakis-(trifluoromethanesulfonato)-aurate Anion: Syntheses and Properties of M[Au(CF$_3$SO$_3$)$_4$] (M = Li--Rb, Ag)," Z. Anorg. Allg. Chem., vol. 639, iss. 3-4, pp. 485-492, 2013.
    @Article{Logemann2013, Title = {The Tetrakis-(trifluoromethanesulfonato)-aurate Anion: Syntheses and Properties of M[Au(CF$_3$SO$_3$)$_4$] (M = Li--Rb, Ag)},
      Author = {Logemann, Christian and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Z. Anorg. Allg. Chem.},
      Pages = {485--492},
      Volume = {639},
      Year = {2013},
      Month = mar, Number = {3-4},
      Abstract = {The reaction of Au(OH)3 and trifluoromethanesulfonic acid (triflic acid) in the presence of M2CO3 (M = Li, Na, K, Rb) and Ag(CF3SO3), respectively, yielded yellow single crystals of M[Au(CF3SO3)4] (M = Li, Na, K, Rb, Ag). They exhibit the [Au(CF3SO3)4] anion with the gold atom in a square-planar coordination of four monodentate triflate ions. The structural characteristics of the anion are well reproduced by theoretical calculations that allowed also for a reliable assignment of observed IR energies. Charge compensation for the anions is achieved by different M+ counter cations. According to their coordination requirements different crystal structures are adopted. For M = Li, Na, the compounds are triclinic [M = Li/Na: triclinic, P$\bar{1}$, Z = 1, a = 509.92(2)/525.43(2), b = 854.08(3)/902.08(4), c = 1044.67(4)/1080.28(5) pm, = 94.006(2)/104.367(2)degrees, = 92.935(2)/93.602(3)degrees, = 93.841(2)/90.706(2)degrees, V = 452.12(3)/494.83(4) angstrom 3] and octahedral coordination of the cations is observed. The monoclinic Ag[Au(CF3SO3)4] [C2/c, Z = 4, a = 2218.83(5), b = 499.19(1), c = 1751.73(4) pm, = 104.736(1)degrees, V = 1876.43(7) angstrom 3] shows the Ag+ ion in trigonal prismatic surrounding of oxygen atoms. A coordination number of eight is found for K[Au(CF3SO3)4] [orthorhombic, Pbcn, Z = 4, a = 904.32(4), b = 1050.64(4), c = 2120.71(9) pm, V = 2014.92(15) angstrom 3] and also for Rb[Au(CF3SO3)4] [monoclinic, P21/n, Z = 4, a = 919.80(3), b = 2121.77(6), c = 1083.40(3) pm, = 90.120(2)degrees, V = 2114.36(11) angstrom 3]. In both cases the [MO8] polyhedra have dodecahedral shape. The thermal decomposition of selected compounds was monitored up to 1050 degrees C and shows that a mixture of elemental gold and the respective alkaline metal sulfate is the residue. For M = Ag elemental silver is formed instead of a sulfate.},
      Url = {http://dx.doi.org/10.1002/zaac.201300025} }
  • [inproceedings] bibtex
    T. Klüner, "Numerical aspects of wave packet calculations: the program package DYN5D," in Proc. Modern computational science 12, Oldenburg, 2012, pp. 349-360.
    @InProceedings{Kluener2012, Title = {Numerical aspects of wave packet calculations: the program package DYN5D},
      Author = {Klüner, Thorsten},
      Booktitle = {Modern computational science 12},
      Year = {2012},
      Address = {Oldenburg},
      Editor = {Reinhard Leidl and Alexander K. Hartmann},
      Pages = {349--360} }
  • C. Logemann, T. Klüner, und M. S. Wickleder, "The Elusive Tetrasulfate Anion [S$_4$O$_13$]^2-," Angew. Chem., Int. Ed., vol. 51, iss. 20, pp. 4997-5000, 2012.
    @Article{Logemann2012, Title = {The Elusive Tetrasulfate Anion [S$_4$O$_13$]^{2-}},
      Author = {Logemann, Christian and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Angew. Chem., Int. Ed.},
      Pages = {4997--5000},
      Volume = {51},
      Year = {2012},
      Number = {20},
      Url = {http://dx.doi.org/10.1002/anie.201108206} }
  • L. V. Moskaleva, V. Zielasek, T. Klüner, K. M. Neyman, und M. Bäumer, "CO oxidation by co-adsorbed atomic O on the Au(321) surface with Ag impurities: A mechanistic study from first-principles calculations," Chem. Phys. Lett., vol. 525-26, pp. 87-91, 2012.
    @Article{Moskaleva2012, Title = {CO oxidation by co-adsorbed atomic O on the Au(321) surface with Ag impurities: A mechanistic study from first-principles calculations},
      Author = {Moskaleva, Lyudmila V. and Zielasek, Volkmar and Klüner, Thorsten and Neyman, Konstantin M. and Bäumer, Marcus},
      Journal = {Chem. Phys. Lett.},
      Pages = {87--91},
      Volume = {525-26},
      Year = {2012},
      Month = feb, Abstract = {The reaction routes between co-adsorbed CO and O on kinked Au(321) slabs are analyzed theoretically. Complexes of vicinal type react most easily with calculated barriers from 0.05 to 0.3 eV, whereas the more strongly co-adsorbed geminal structures do not react directly unless surface oxygen is present in excess. Generally, the activation energy of CO2 formation from vicinal complexes remains low and that from geminal complexes increases, when Ag impurities are introduced. Our results can be generalized to other rough gold surfaces, particularly, helping to understand the formation of CO2 above 200 K, as observed in the temperature programmed desorption studies of nanoporous gold, a monolithic nano-structured gold catalyst. (C) 2011 Elsevier B. V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.cplett.2011.12.050} }
  • N. Wache, A. Scholten, T. Klüner, K. Koch, und J. Christoffers, "Turning On Fluorescence with Thiols - Synthetic and Computational Studies on Diaminoterephthalates and Monitoring the Switch of the Ca^2+ Sensor Recoverin," Eur. J. Org. Chem., iss. 29, pp. 5712-5722, 2012.
    @Article{Wache2012, Title = {Turning On Fluorescence with Thiols - Synthetic and Computational Studies on Diaminoterephthalates and Monitoring the Switch of the Ca^{2+} Sensor Recoverin},
      Author = {Wache, Nina and Scholten, Alexander and Klüner, Thorsten and Koch, Karl-Wilhelm and Christoffers, Jens},
      Journal = {Eur. J. Org. Chem.},
      Pages = {5712--5722},
      Year = {2012},
      Month = oct, Number = {29},
      Abstract = {The fluorescence of maleimide-functionalized diaminoterephthalate derivatives (NiWa Orange) is turned on by the conjugate addition of thiols. Three new representatives of this class of dyes with emission at 560 nm were synthesized from succinyl succinates. The mechanism of turning on the fluorescence was investigated by computational studies. Radiationless transition to an energetically low-lying excited state by a nonadiabatic interaction was the mechanism leading to absence of fluorescence prior to the reaction of the probe with its molecular target. This concept was proven by labeling cysteine-containing peptides and proteins. For example, the single cysteine residue at position 39 of the neuronal calcium sensor protein recoverin binds to NiWa Orange and turns on its fluorescence. The Ca2(+)-dependent Forster resonance energy transfer (FRET) process from a tryptophan residue in proximity to Cys39-bound NiWa Orange was used for the determination of differences in Ca2(+)-binding affinities of myristoylated and nonmyristoylated recoverin.},
      Url = {http://dx.doi.org/10.1002/ejoc.201200879} }
  • C. Logemann, D. Gunzelmann, T. Klüner, J. Senker, und M. S. Wickleder, "Reactions with Oleum under Harsh Conditions: Characterization of the Unique [M(S$_2$O$_7$)$_3$]^2- Ions (M=Si, Ge, Sn) in A$_2$[M(S$_2$O$_7$)$_3$] (A=NH$_4$, Ag)," Chem. Eur. J., vol. 18, iss. 48, pp. 15495-15503, 2012.
    @Article{Logemann2012a, Title = {Reactions with Oleum under Harsh Conditions: Characterization of the Unique [M(S$_2$O$_7$)$_3$]^{2-} Ions (M=Si, Ge, Sn) in A$_2$[M(S$_2$O$_7$)$_3$] (A=NH$_4$, Ag)},
      Author = {Logemann, Christian and Gunzelmann, Daniel and Klüner, Thorsten and Senker, Jürgen and Wickleder, Mathias S.},
      Journal = {Chem. Eur. J.},
      Pages = {15495--15503},
      Volume = {18},
      Year = {2012},
      Month = nov, Number = {48},
      Abstract = {The reactions of group 14 tetrachlorides MCl4 (M=Si, Ge, Sn) with oleum (65?% SO3) at elevated temperatures lead to the unique complex ions [M(S2O7)3]2-, which show the central M atoms in coordination with three chelating S2O72- groups. The mean distances M?O within the anions increase from 175.6(2)177.5(2) pm (M=Si) to 186.4(4)187.7(4) pm (M=Ge) to 201.9(2)203.5(2) pm (M=Sn). These distances are reproduced well by DFT calculations. The same calculations show an increasing positive charge for the central M atom in the row Si, Ge, Sn, which can be interpreted as the decreasing covalency of the M?O bonds. For the silicon compound (NH4)2[Si(S2O7)3], 29Si solid-state NMR measurements have been performed, with the results showing a signal at -215.5 ppm for (NH4)2[Si(S2O7)3], which is in very good agreement with theoretical estimations. In addition, the vibrational modes within the [MO6] skeleton have been monitored by Raman spectroscopy for selected examples, and are well reproduced by theory. The charge balance for the [M(S2O7)3]2- ions is achieved by monovalent A+ counter ions (A=NH4, Ag), which are implemented in the syntheses in the form of their sulfates. The sizes of the A+ ions, that is, their coordination requirements, cause the crystallographic differences in the crystal structures, although the complex [M(S2O7)3]2- ions remain essentially unaffected with the different A+ ions. Furthermore, the nature of the A+ ions influences the thermal behavior of the compounds, which has been monitored for selected examples by thermogravimetric differential thermal analysis (DTA/TG) and XRD measurements.},
      Url = {http://dx.doi.org/10.1002/chem.201202344} }
  • J. Mitschker und T. Klüner, "New Insight into CO Photodesorption from C$_60$," J. Phys. Chem. A, vol. 116, iss. 46, pp. 11211-11218, 2012.
    @Article{Mitschker2012, Title = {New Insight into CO Photodesorption from C$_60$},
      Author = {Mitschker, Jan and Klüner, Thorsten},
      Journal = {J. Phys. Chem. A},
      Pages = {11211--11218},
      Volume = {116},
      Year = {2012},
      Month = nov, Number = {46},
      Abstract = {We,report on new results concerning the interaction of CO with C-60 in the electronic ground state and an electronically excited state. We found that the energetically most favorable geometries are vertical or horizontal in the ground state but in the excited state the molecule is tilted by about 40 degrees. The two-dimensional potential energy surfaces of these states were used to simulate the photodesorption process induced by a short laser pulse. An interesting desorption. mechanism Was found, leading to a bimodal velocity distribution for each rotational quantum state if the molecule starts from the rovibronic ground state.},
      Url = {http://dx.doi.org/10.1021/jp305133z} }
  • W. Yim und T. Klüner, "Electronic and lattice instability and its relaxation mechanism in Pt-Co interfaces," Phys. Rev. B, vol. 85, iss. 3, p. 035435, 2012.
    @Article{Yim2012, Title = {Electronic and lattice instability and its relaxation mechanism in Pt-Co interfaces},
      Author = {Yim, Wai-Leung and Klüner, Thorsten},
      Journal = {Phys. Rev. B},
      Pages = {035435},
      Volume = {85},
      Year = {2012},
      Month = jan, Number = {3},
      Abstract = {Lattice instabilities of bimetallic Pt-Co interfaces have been examined within density functional theory. We discovered that the lattice instability and electron instability in momentum space were strongly correlated on bimetallic interfaces. The lattice instability of the Pt-Co interface was illustrated by Fermi surface nesting in two dimensions, and the nesting vector along the (110) direction in electron momentum space has been identified. The predicted reconstruction-induced Pt diffusion trend was in excellent agreement with previously obtained experimental findings.},
      Url = {http://dx.doi.org/10.1103/PhysRevB.85.035435} }
  • E. Asplund und T. Klüner, "Optimal control of open quantum systems: A combined surrogate Hamiltonian optimal control theory approach applied to photochemistry on surfaces," J. Chem. Phys., vol. 136, iss. 12, p. 124118, 2012.
    @Article{Asplund2012, Title = {Optimal control of open quantum systems: A combined surrogate Hamiltonian optimal control theory approach applied to photochemistry on surfaces},
      Author = {Asplund, Erik and Klüner, Thorsten},
      Journal = {J. Chem. Phys.},
      Pages = {124118},
      Volume = {136},
      Year = {2012},
      Month = mar, Number = {12},
      Abstract = {In this paper, control of open quantum systems with emphasis on the control of surface photochemical reactions is presented. A quantum system in a condensed phase undergoes strong dissipative processes. From a theoretical viewpoint, it is important to model such processes in a rigorous way. In this work, the description of open quantum systems is realized within the surrogate Hamiltonian approach [R. Baer and R. Kosloff, J. Chem. Phys. 106, 8862 (1997)]. An efficient and accurate method to find control fields is optimal control theory (OCT) [W. Zhu, J. Botina, and H. Rabitz, J. Chem. Phys. 108, 1953 (1998); Y. Ohtsuki, G. Turinici, and H. Rabitz, J. Chem. Phys. 120, 5509 (2004)]. To gain control of open quantum systems, the surrogate Hamiltonian approach and OCT, with time-dependent targets, are combined. Three open quantum systems are investigated by the combined method, a harmonic oscillator immersed in an ohmic bath, CO adsorbed on a platinum surface, and NO adsorbed on a nickel oxide surface. Throughout this paper, atomic units, i.e., h = m(e) = e = a(0) = 1, have been used unless otherwise stated. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3698289]},
      Url = {http://dx.doi.org/10.1063/1.3698289} }
  • C. Logemann, T. Klüner, und M. S. Wickleder, "Synthesis and Characterization of the Trisulfate Pb[S$_3$O$_10$] and Theoretical Analysis of H$_2$S$_3$O$_10$," Z. Anorg. Allg. Chem., vol. 638, iss. 5, pp. 758-762, 2012.
    @Article{Logemann2012b, Title = {Synthesis and Characterization of the Trisulfate Pb[S$_3$O$_10$] and Theoretical Analysis of H$_2$S$_3$O$_10$},
      Author = {Logemann, Christian and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Z. Anorg. Allg. Chem.},
      Pages = {758--762},
      Volume = {638},
      Year = {2012},
      Month = apr, Number = {5},
      Abstract = {The reaction of (NH4)2PbCl6 and fuming sulfuric acid (65?% SO3) in a sealed glass tube at 250 degrees C led to colorless single crystals of Pb[S3O10] (orthorhombic, Pbcn, Z = 4, a = 10.9908(4), b = 8.5549(3), c = 8.0130(3) angstrom, V = 753.42(5) angstrom 3). The compound shows a three-dimensional linkage of the tenfold oxygen coordinated Pb2+ ions and exhibits the unusual trisulfate anion, [S3O10]2, that consists of three vertex connected [SO4] tetrahedra. The distances SO within the SOS bridges of the anion are remarkable asymmetric with distances of 155 and 169 pm, respectively. This structural feature is well reproduced by calculations on a PBE0/cc-pVTZ and a MP2/cc-pVTZ level of theory. Similar calculations allow also for an inspection of the yet unknown corresponding acid, H2S3O10. Also for this acid non-symmetric SOS bridges are predicted. The thermal behavior of Pb[S3O10] is characterized by the loss of two equivalents of SO3 at low temperature and the decomposition of intermediate Pb[SO4] at higher temperature.},
      Url = {http://dx.doi.org/10.1002/zaac.201100533} }
  • K. Neuschulz, M. Penning, L. Gross, T. Klüner, und M. S. Wickleder, "Opening the paddlewheel: unusual coordination of [Mo$_2$] dumbbells in the chain structures of A[Mo$_2$(CF$_3$SO$_3$)$_5$] $\cdot$ 2CF$_3$SO$_3$H (A = Na, Rb, Cs)," Dalton Trans., vol. 41, iss. 15, pp. 4685-4691, 2012.
    @Article{Neuschulz2012, Title = {Opening the paddlewheel: unusual coordination of [Mo$_2$] dumbbells in the chain structures of A[Mo$_2$(CF$_3$SO$_3$)$_5$] $\cdot$ 2CF$_3$SO$_3$H (A = Na, Rb, Cs)},
      Author = {Neuschulz, Kai and Penning, Miriam and Gross, Lynn and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Dalton Trans.},
      Pages = {4685--4691},
      Volume = {41},
      Year = {2012},
      Number = {15},
      Abstract = {The reaction of Mo(II) acetate, concentrated triflic acid and the alkaline metal triflates A(CF3SO3) (A = Na, Rb, Cs) in sealed glass ampoules at 110 degrees C yielded red single crystals of A[Mo-2(CF3SO3)(5)]center dot 2CF(3)SO(3)H (A = Na: triclinic, P-1, Z = 4, a = 13.714(1) angstrom, b = 14.339(1) angstrom, c = 21.340(2) angstrom, alpha = 81.78(1)degrees, beta = 75.21(1)degrees, gamma = 62.65(1)degrees; A = Rb/Cs: monoclinic, P2(1)/m, Z = 2, a = 11.561(1)/11.584(1) angstrom, b = 14.817(1)/14.9472(8) angstrom, c = 11.6208(1)/11.744(1) angstrom, beta = 112.38(1)/113.48(1)degrees). The crystal structures contain dumbbell shaped [Mo-2] moieties surrounded by three chelating and four monodentate triflate anions leading to an opening of the typical paddlewheel fragment at one of its edges. The monodentate triflate anions are connected to further [Mo-2] dumbbells leading to infinite anionic chains according to (1)(infinity)[Mo-2(CF3SO3)(3/1)(CF3SO3)(4/2)](-). The charge balance is achieved by the alkaline metal ions that are additionally coordinated by triflic acid molecules. Theoretical investigations were preformed on the open paddlewheel fragment and are in good agreement with the experimental findings. According to DTA/TG measurements and the XRD investigations the decomposition of the compounds occurs in multiple steps and leads to MoO2 and A(2)MoO(4).},
      Url = {http://dx.doi.org/10.1039/c2dt12196d} }
  • U. Betke, W. Dononelli, T. Klüner, und M. S. Wickleder, "ReO$_2$Cl(S$_2$O$_7$), a Molecular Disulfate," Angew. Chem., Int. Ed., vol. 50, iss. 51, pp. 12361-12363, 2011.
    @Article{Betke2011, Title = {ReO$_2$Cl(S$_2$O$_7$), a Molecular Disulfate},
      Author = {Betke, Ulf and Dononelli, Wilke and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Angew. Chem., Int. Ed.},
      Pages = {12361--12363},
      Volume = {50},
      Year = {2011},
      Number = {51},
      Url = {http://dx.doi.org/10.1002/anie.201105457} }
  • C. Logemann, T. Klüner, und M. S. Wickleder, "The [Si(S$_2$O$_7$)$_3$]^2- Anion: A First Example of Octahedral Silicon Coordination by Three Chelating Inorganic Ligands," Chem. Eur. J., vol. 17, iss. 3, pp. 758-760, 2011.
    @Article{Logemann2011, Title = {The [Si(S$_2$O$_7$)$_3$]^{2-} Anion: A First Example of Octahedral Silicon Coordination by Three Chelating Inorganic Ligands},
      Author = {Logemann, Christian and Klüner, Thorsten and Wickleder, Mathias S.},
      Journal = {Chem. Eur. J.},
      Pages = {758--760},
      Volume = {17},
      Year = {2011},
      Number = {3},
      Url = {http://dx.doi.org/10.1002/chem.201002619} }
  • F. Behler, F. Habecker, W. Saak, T. Klüner, und J. Christoffers, "Synthesis of Benzo[c]azocanones and Indeno[1,2-b]pyrroles from Oxoindanecarboxylates," Eur. J. Org. Chem., iss. 22, pp. 4231-4240, 2011.
    @Article{Behler2011, Title = {Synthesis of Benzo[c]azocanones and Indeno[1,2-b]pyrroles from Oxoindanecarboxylates},
      Author = {Behler, Florian and Habecker, Florian and Saak, Wolfgang and Klüner, Thorsten and Christoffers, Jens},
      Journal = {Eur. J. Org. Chem.},
      Pages = {4231--4240},
      Year = {2011},
      Month = aug, Number = {22},
      Abstract = {Ethyl 1-oxo-indane-2-carboxylate with a 1,4-diketone motif gave a benzo[c]azocane-1-one derivative - an eight-membered ring lactam - in a bismuth-mediated ring-expansion reaction with methylamine (40% yield). Yields with other primary amines were significantly lower. The ester function in the heterocyclic product could be saponified to give the free carboxylic acid, which was further amidated with para-bromoaniline. The molecular structure of the latter was established by X-ray single-crystal analysis. Benzo[c]azo-canones exist in two diastereoisomeric conformations, causing double signal sets in the NMR spectra. Slow interconversion between these conformers was proved by EXSY NMR spectroscopy. Moreover, a conformational analysis by DFT calculations revealed the two diastereoisomers to be boat conformers that interconvert through a twist conformer. The maximum barrier for this process was calculated to be approximately 70 kJ/mol. Reaction of the corresponding methyl 1-oxoindane-2-carboxylate with methylamine gave the benzo[c]azocanone in lower yield. A spirolactam and an indeno[1,2-b]pyrrole were formed as further products. When using an indanone-derived 1,4-diketone without an ester function, several primary amines could be used in a bismuth-catalyzed Paal-Knorr reaction to give indeno[1,2-b]pyrrole derivatives with up to quantitative yields in several cases. Attempts to synthesize a caprolactam derivative from a cyclobutanone derived beta-oxo ester with 1,4-diketone motif were unsuccessful.},
      Url = {http://dx.doi.org/10.1002/ejoc.201100289} }
  • L. V. Moskaleva, S. Röhe, A. Wittstock, V. Zielasek, T. Klüner, K. M. Neyman, und M. Bäumer, "Silver residues as a possible key to a remarkable oxidative catalytic activity of nanoporous gold," Phys. Chem. Chem. Phys., vol. 13, iss. 10, pp. 4529-4539, 2011.
    @Article{Moskaleva2011, Title = {Silver residues as a possible key to a remarkable oxidative catalytic activity of nanoporous gold},
      Author = {Moskaleva, Lyudmila V. and Röhe, Sarah and Wittstock, Arne and Zielasek, Volkmar and Klüner, Thorsten and Neyman, Konstantin M. and Bäumer, Marcus},
      Journal = {Phys. Chem. Chem. Phys.},
      Pages = {4529--4539},
      Volume = {13},
      Year = {2011},
      Number = {10},
      Abstract = {Recently, several forms of unsupported gold were shown to display a remarkable activity to catalyze oxidation reactions. Experimental evidence points to the crucial role of residual silver present in very small concentrations in these novel catalysts. We focus on the catalytic properties of nanoporous gold (np-Au) foams probed via CO and oxygen adsorption/co-adsorption. Experimental results are analyzed using theoretical models represented by the flat Au(111) and the kinked Au(321) slabs with Ag impurities. We show that Ag atoms incorporated into gold surfaces can facilitate the adsorption and dissociation of molecular oxygen on them. CO adsorbed on top of 6-fold coordinated Au atoms can in turn be stabilized by co-adsorbed atomic oxygen by up to 0.2 eV with respect to the clean unsubstituted gold surface. Our experiments suggest a linking of that most strongly bound CO adsorption state to the catalytic activity of np-Au. Thus, our results shed light on the role of silver admixtures in the striking catalytic activity of unsupported gold nanostructures.},
      Url = {http://dx.doi.org/10.1039/c0cp02372h} }
  • E. Asplund und T. Klüner, "Optimal Control of Open Quantum Systems Applied to the Photochemistry of Surfaces," Phys. Rev. Lett., vol. 106, iss. 14, p. 140404, 2011.
    @Article{Asplund2011, Title = {Optimal Control of Open Quantum Systems Applied to the Photochemistry of Surfaces},
      Author = {Asplund, Erik and Klüner, Thorsten},
      Journal = {Phys. Rev. Lett.},
      Pages = {140404},
      Volume = {106},
      Year = {2011},
      Month = apr, Number = {14},
      Abstract = {A quantum system in a condensed phase undergoes strong dissipative processes. The last decades have seen the rise of experimental and theoretical approaches for gaining control over dissipative phenomena. From a theoretical viewpoint it is important to model such processes in a rigorous way. An efficient and accurate method to find control fields is optimal control theory (OCT). In this Letter, a control scheme relying on OCT with time-dependent targets is employed to minimize dissipation, modeled within the surrogate Hamiltonian approach, on adsorbate-surface systems.},
      Url = {http://dx.doi.org/10.1103/PhysRevLett.106.140404} }
  • M. Mehring und T. Klüner, "Understanding surface photochemistry from first principles: The case of CO-TiO$_2$(110)," Chem. Phys. Lett., vol. 513, iss. 4-6, pp. 212-217, 2011.
    @Article{Mehring2011, Title = {Understanding surface photochemistry from first principles: The case of CO-TiO$_2$(110)},
      Author = {Mehring, Matthias and Klüner, Thorsten},
      Journal = {Chem. Phys. Lett.},
      Pages = {212--217},
      Volume = {513},
      Year = {2011},
      Month = sep, Number = {4-6},
      Abstract = {First results concerning laser-induced photodesorption of CO molecules from a TiO2(110) surface are presented. For the laser-driven process an internal 5 sigma -> 2 pi*-excitation within the CO molecule is assumed. In the ground state, electrostatic forces dominate the interaction between the adsorbate and the surface. In contrast, in the excited state, the CO molecule rotates by 180 degrees forming a covalent bond with the oxygen atom pointing downwards to the surface. Subsequent quantum dynamical simulations based on two-dimensional ab initio potential energy surfaces revealed a novel desorption mechanism, which is traced back to unusual interplay of electronic ground and excited state, respectively. (C) 2011 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.cplett.2011.07.093} }
  • J. Mitschker und T. Klüner, "Adsorption and photodesorption of CO from single C$_60$ molecules studied from first principles," Chem. Phys. Lett., vol. 514, iss. 1-3, pp. 83-87, 2011.
    @Article{Mitschker2011, Title = {Adsorption and photodesorption of CO from single C$_60$ molecules studied from first principles},
      Author = {Mitschker, Jan and Klüner, Thorsten},
      Journal = {Chem. Phys. Lett.},
      Pages = {83--87},
      Volume = {514},
      Year = {2011},
      Month = sep, Number = {1-3},
      Abstract = {We report on first ab initio results concerning the photodesorption of CO from a single C-60 fullerene. The weak interaction makes the use of computationally demanding electron correlation methods mandatory and we present various approaches for reducing the computational effort. The calculated adsorption energy amounts to -8.5 kJ mol(-1) for the electronic ground state. The photodesorption is assumed to result from a 5 sigma -> 2 pi(star) excitation in the adsorbate. The interaction in the excited state is stronger and leads to an Antoniewicz-like desorption mechanism. We treated the desorption process quantum dynamically and calculated desorption probabilities and velocity distributions of the desorbing molecules. (C) 2011 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.cplett.2011.08.013} }
  • W. Yim und T. Klüner, "Lattice Stability of Si[100] Wires From First Principles," J. Phys. Chem. C, vol. 115, iss. 8, pp. 3286-3290, 2011.
    @Article{Yim2011, Title = {Lattice Stability of Si[100] Wires From First Principles},
      Author = {Yim, Wai-Leung and Klüner, Thorsten},
      Journal = {J. Phys. Chem. C},
      Pages = {3286--3290},
      Volume = {115},
      Year = {2011},
      Month = mar, Number = {8},
      Abstract = {Quantum many-body effects such as electron-phonon coupling are generally enhanced in reduced dimensions. However, the influence of many body effects on the structural stability is often underestimated. We used ab initio phonon and molecular dynamics calculations to illustrate the strong electron-phonon coupling in metallic Si[100] wires. We found that the smallest crystalline Si[100] wire is a sharp-corner Si-25 wire. Electron-phonon coupling favors a tilted orientation of Si-Si bond pairs at the walls of the wires. Both sharp- and cut-corner Si [100] wires are thermally stable. A partial charge density near the Fermi energy was calculated to reveal the chemical reactivity of different Si sites. Surprisingly, the most reactive sites of cut corner Si[100] were located at the subsurface atoms at the groove sites adjacent to the corners of the walls. Our work predicts the crystallinity of nanowire structures which will find further applications particularly for the systems sensitive to crystalline-to-amorphous transition.},
      Url = {http://dx.doi.org/10.1021/jp110500d} }
  • T. W. T. Muesmann, C. Zitzer, A. Mietrach, T. Klüner, J. Christoffers, und M. S. Wickleder, "Para-Benzene disulfonic acid and its tetrachloro and tetrafluoro derivatives-studies towards polyhalogenated metal-organic-frameworks with sulfo analogues of terephthalic acid," Dalton Trans., vol. 40, iss. 13, pp. 3128-3141, 2011.
    @Article{Muesmann2011, Title = {para-Benzene disulfonic acid and its tetrachloro and tetrafluoro derivatives-studies towards polyhalogenated metal-organic-frameworks with sulfo analogues of terephthalic acid},
      Author = {Muesmann, Thomas W. T. and Zitzer, Christina and Mietrach, Andrea and Klüner, Thorsten and Christoffers, Jens and Wickleder, Mathias S.},
      Journal = {Dalton Trans.},
      Pages = {3128--3141},
      Volume = {40},
      Year = {2011},
      Month = apr, Number = {13},
      Abstract = {We developed convenient synthetic routes for the preparation of para-benzene disulfonic acid (H2BDS) and its tetrachloro (H2BDSCl4) and tetrafluoro (H2BDSF4) derivatives. The reaction of these acids with zinc nitrate in DMF led to single crystals of [Zn(BDS)(DMF)(2)] (triclinic, P (1) over bar, Z = 2, a = 976.62(4), b = 986.85(4), c = 1014.40(4), alpha = 69.106(2)degrees, beta = 68.746(2)degrees, gamma = 86.295(2)degrees, wR(2) = 0.0627), [Zn(BDSCl4)(DMF)(4)] (triclinic, P (1) over bar, Z = 1, a = 831.5(1), b = 905.2(1), c = 989.6(1), alpha = 90.44(2)degrees, beta = 91.41 (2)degrees, gamma = 106.72(2)degrees, wR(2) = 0.0635), and [Zn(BDSF4)(DMF)(4)] (monoclinic, P2(1)/c, Z = 2, a = 889.01(3), b = 968.91(3), c = 1633.07(5) pm, beta = 106.524(2)degrees, wR(2) = 0.0948). While [Zn(BDS)(DMF)(2)] exhibits a layer structure, the disulfonate linkers connect the zinc ions into chains in the crystal structures of [Zn(BDSCl4)(DMF)(4)] and [Zn(BDSF4)(DMF)(4)]. Thermoanalytical investigations revealed that desolvation of the compounds occurs in a temperature range between 100 and 200 degrees C. The solvent free sulfonates show remarkably high stabilities, [Zn(BDS)(DMF)(2)] is stable up to nearly 600 degrees C. The halogenated acids were also used to prepare copper salts from aqueous solutions and Cu-2(OH)(2)(CO3) (malachite) as a copper source. The crystal structure of [Cu(H2O)(6)](BDSF4) (triclinic, P (1) over bar, Z = 1, a = 510.45(2), b = 744.68(3), c = 1077.77(4) pm, alpha = 85.627 (2)degrees, beta = 77.449 (2)degrees, gamma = 76.015 (2)degrees) exhibits complex cations and uncoordinated sulfonate anions, while in [Cu(BDSCl4)(H2O)(4)] (orthorhombic, Pnma, Z = 4, a = 721.27(2), b = 2147.81(6), c = 979.42(3) pm) the Cu2+ ions are linked to infinite chains in the crystal structure. The most interesting structural feature of [Cu(BDSCl4)(H2O)(4)] is the significant deviation from planarity of the disulfonate dianion. Theoretical investigations revealed that a boat conformation is favoured due to steric hindrance in cases where a syn coordination of the sulfonate groups occurs. The thermal behaviour of the copper compounds was also investigated by DTA/TG measurements and X-ray powder diffraction.},
      Url = {http://dx.doi.org/10.1039/c0dt01223h} }
  • [incollection] bibtex | Dokument aufrufen Dokument aufrufen
    W. -L. Yim und T. Klüner, "H$_2$ Carrying Capacity by Considering Charging and Discharging Processes - Case Studies on Small Carbon- and Boron Nanotubes," in High Performance Computing in Science and Engineering ‘09, Nagel, W. E., Kröner, D. H., und Resch, M. M., Eds., Springer International Publishing, 2010.
    @InCollection{Yim2010a, Title = {H$_2$ Carrying Capacity by Considering Charging and Discharging Processes - Case Studies on Small Carbon- and Boron Nanotubes},
      Author = {W.-L. Yim and Thorsten Klüner},
      Booktitle = {High Performance Computing in Science and Engineering ‘09},
      Publisher = {Springer International Publishing},
      Year = {2010},
      Editor = {Nagel, Wolfgang E. and Kröner, Dietmar H. and Resch, Michael M.},
      Url = {http://dx.doi.org/10.1007 / 978-3-642-04665-0_7} }
  • [inproceedings] bibtex
    T. Klüner, "Numerical aspects of wave packet calculations: the program package DYN5D," in Proc. Modern computational science 10, Oldenburg, 2010, pp. 327-358.
    @InProceedings{Kluener2010a, Title = {Numerical aspects of wave packet calculations: the program package DYN5D},
      Author = {Klüner, Thorsten},
      Booktitle = {Modern computational science 10},
      Year = {2010},
      Address = {Oldenburg},
      Editor = {Reinhard Leidl; Alexander K. Hartmann (eds.).},
      Pages = {327--358} }
  • I. Brand, M. Nullmeier, T. Klüner, R. Jogireddy, J. Christoffers, und G. Wittstock, "Structural Analysis of HS(CD$_2$)$_12$(O-CH$_2$-CH$_2$)$_6$OCH$_3$ Monolayers on Gold by Means of Polarization Modulation Infrared Reflection Absorption Spectroscopy. Progress of the Reaction with Bromine," Langmuir, vol. 26, iss. 1, pp. 362-370, 2010.
    @Article{Brand2010, Title = {Structural Analysis of HS(CD$_2$)$_12$(O-CH$_2$-CH$_2$)$_6$OCH$_3$ Monolayers on Gold by Means of Polarization Modulation Infrared Reflection Absorption Spectroscopy. Progress of the Reaction with Bromine},
      Author = {Brand, Izabella and Nullmeier, Martina and Klüner, Thorsten and Jogireddy, Rajamalleswaramma and Christoffers, Jens and Wittstock, Gunther},
      Journal = {Langmuir},
      Pages = {362--370},
      Volume = {26},
      Year = {2010},
      Month = jan, Number = {1},
      Abstract = {A self-assembled monolayer (SAM) on gold was formed with specifically perdeuterated hexaethylene glycol-terminated alkanethiol HS(CD2)(12)(O-CH2-CH2)(6)OCH3 (D-OEG). The structure of the d-alkane and the oligoethylene glycol (OEG) parts of the molecule in a SAM was Studied by means of polarization modulation infrared reflection absorption spectroscopy. The D-OEG monolayers are highly ordered and exist in a crystalline phase. The d-alkane chain adopts an all-trans conformation. Both, the d-alkane chain and long axis of the OEG part make an angle of 26.0 degrees +/- 1.5 degrees with respect to the surface normal, a value characteristic for the Lilt of solid n-alkane thiols in the SAMs on Au. The positions of nu(as)(COC) and CH2 wagging and rocking modes indicate a helical arrangement of the OEG chains. The D-OEG SAMs were exposed to 25 mu M Br-2 in two ways: (i) by immersion into the Br-2 solution and (ii) in the galvanic cell Au vertical bar D-OEG SAM vertical bar 25 mu M Br-2 + 0.1 M Na2SO4 parallel to 50 mu M KBr + 0.1 M Na2SO4 vertical bar Au. In the galvanic cell, theoxidant(Br-2)is scavenged by a heterogeneous electron transfer reaction, slowing the reaction of D-OEG with Br-2. The slow progress of the reaction with Br-2 allowed us to draw Conclusions about molecular rearrangements taking place during this reaction. The reaction with Br-2 starts on boundaries and/or defects present in the SAM. First, at the defect place, the alpha-C atom of the OEG chain reacts with Br-2 and the OEG part or the molecule is removed from the monolayer. In consequence an increase in disorder in the OEG part of the SAM is observed. The same mechanism of the reaction with Br-2 is applied for the d-dodecane alkanethiol part of the molecule. This reaction is slow, thus the order and the tilt of the hydrocarbon chain changes only a little during the reaction time.},
      Url = {http://dx.doi.org/10.1021/la9020993} }
  • T. Klüner, "Photodesorption of diatomic molecules from surfaces: A theoretical approach based on first principles," Prog. Surf. Sci., vol. 85, iss. 5-8, pp. 279-345, 2010.
    @Article{Kluener2010, Title = {Photodesorption of diatomic molecules from surfaces: A theoretical approach based on first principles},
      Author = {Klüner, Thorsten},
      Journal = {Prog. Surf. Sci.},
      Pages = {279--345},
      Volume = {85},
      Year = {2010},
      Month = may, Number = {5-8},
      Abstract = {Photodesorption of small molecules from surfaces is one of the most fundamental processes in surface photochemistry. Despite its apparent simplicity, a microscopic understanding beyond a qualitative picture still poses a true challenge for theory. While the dynamics of nuclear motion can be treated on various levels of sophistication, all approaches suffer from the lack of sufficiently accurate potential energy surfaces, in particular for electronically excited states involved in the desorption scenario. In the last decade, a systematic and accurate methodology has been developed which allows a reliable calculation of accurate ground and excited state potential energy surfaces (PES) for different adsorbate-substrate systems. These potential energy surfaces serve as a prerequisite for subsequent quantum dynamical wave packet calculations, which allow for a direct simulation of experimentally observable quantities such as quantum state resolved velocity distributions. In the first part of this review, we will focus on scalar properties of desorbing diatomic molecules from insulating surfaces, where we also present a recently developed strategy of obtaining accurate potential energy surfaces using quantum chemical approaches. In general, diatomic molecules on large band gap materials such as oxide surfaces are studied which allows the use of sufficiently large cluster models and accurate ab initio methods beyond density functional theory (DFT). In the second part, we will focus on the vectorial aspects of the dynamics of nuclear motion and present simulations of experimentally accessible observables such as velocity distributions, Doppler profiles and alignment parameters. For each system, the microscopic mechanism of photodesorption is elucidated. We will demonstrate that the driving force of surface photochemistry is strongly dependent on details of the electronic structure of the adsorbate substrate systems. This implies that great caution is advisable if experimental results are interpreted using empirical or semi-empirical models. (C) 2010 Elsevier Ltd. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.progsurf.2010.07.002} }
  • W. Yim und T. Klüner, "Understanding of Adsorption and Catalytic Properties of Bimetallic Pt-Co Alloy Surfaces from First Principles: Insight from Disordered Alloy Surfaces," J. Phys. Chem. C, vol. 114, iss. 15, pp. 7141-7152, 2010.
    @Article{Yim2010, Title = {Understanding of Adsorption and Catalytic Properties of Bimetallic Pt-Co Alloy Surfaces from First Principles: Insight from Disordered Alloy Surfaces},
      Author = {Yim, Wai-Leung and Klüner, Thorsten},
      Journal = {J. Phys. Chem. C},
      Pages = {7141--7152},
      Volume = {114},
      Year = {2010},
      Month = apr, Number = {15},
      Abstract = {Recent experimental studies revealed that the surface compositions of Pt-Co alloy surfaces were tunable by careful control of preparation conditions. This controlled variation of surface composition can be used to modify the chemical activity of the corresponding surfaces. We performed a systematic study on the adsorption and catalytic properties of Pt-Co alloy surfaces based on density functional theory (DFT). We established a protocol to sample the Pt-Co surfaces, in which 4-layer slabs with varying Pt/Co compositions were placed in a hexagonal supercell, exhibiting a (2 x 2) Pt(111) orientation. The characterization of surface properties of these sampled surfaces by DFT calculations was comparable to the available experimental findings. The current work forms a solid basis for extracting complicated chemical information from disordered alloy surfaces, which is essential for the understanding of new materials of increasing complexity.},
      Url = {http://dx.doi.org/10.1021/jp101602b} }
  • I. Parchmann, C. Lienau, T. Klüner, S. Drögemüller, und K. Al-Shamery, ""Can you see atoms?" - a reflection from different scientific perspectives.," CHEMKON, vol. 17, iss. 2, pp. 59-65, 2010.
    @Article{Parchmann2010, Title = {"Can you see atoms?" - a reflection from different scientific perspectives.},
      Author = {Parchmann, Ilka and Lienau, Christoph and Klüner, Thorsten and Drögemüller, Sarah and Al-Shamery, Katharina.},
      Journal = {CHEMKON},
      Pages = {59--65},
      Volume = {17},
      Year = {2010},
      Number = {2},
      Abstract = {This paper deals with the question whether we can "see atoms" and reflects on this form different scientific perspectives. Chem. and phys. explanations about the functioning of the scanning tunnel microscopy technique are given on different levels. Additonally, educational and epistemol. points of view are discussed, both for chem. teaching and teacher education. [on SciFinder(R)]},
      ISSN = {1521-3730},
      Publisher = {Wiley-VCH Verlag GmbH \& Co. KGaA},
      Url = {http://www3.interscience.wiley.com/cgi-bin/fulltext/123349872/PDFSTART} }
  • [inproceedings] bibtex
    T. Klüner, "Numerical aspects of wave packet calculations: the program package DYN5D," in Proc. Modern computational science 09, Oldenburg, 2009, pp. 261-272.
    @InProceedings{Kluener2009, Title = {Numerical aspects of wave packet calculations: the program package DYN5D},
      Author = {Klüner, Thorsten},
      Booktitle = {Modern computational science 09},
      Year = {2009},
      Address = {Oldenburg},
      Editor = {Reinhard Leidl; Alexander K. Hartmann (eds.).},
      Pages = {261--272} }
  • M. Röefzaad, T. Klüner, und I. Brand, "Orientation of the GM1 ganglioside in Langmuir-Blodgett monolayers: a PM IRRAS and computational study," Phys. Chem. Chem. Phys., vol. 11, iss. 43, pp. 10140-10151, 2009.
    @Article{Roeefzaad2009, Title = {Orientation of the GM1 ganglioside in Langmuir-Blodgett monolayers: a PM IRRAS and computational study},
      Author = {Röefzaad, Melanie and Klüner, Thorsten and Brand, Izabella},
      Journal = {Phys. Chem. Chem. Phys.},
      Pages = {10140--10151},
      Volume = {11},
      Year = {2009},
      Number = {43},
      Abstract = {The GM1 ganglioside in the monolayer at the air/water interface shows a liquid expanded-liquid condensed phase transition. Due to a combination of the PM IRRAS results with quantum chemical calculations the structure and orientation of the GM1 molecule in the monolayer on the sub-molecular level is provided. The PM IRRAS studies of GM1 monolayers demonstrate that the phase transition is accompanied by a reorientation of sugar residues with simultaneous changes in the network of hydrogen bonds. The calculation of the IR spectrum of the GM1 molecule allowed us to describe individual nu(as)(COC) modes in sugar residues of the GM1 pentasaccharide. The visualization of the dipole moment vector of each analyzed nu(as)(COC) band allowed us to discuss the orientation of the polar head group of the GM1 in the monolayer. In the liquid expanded state the planes of two sugar residues: beta-Gal-(1-3)-beta Glc-(1-1)-Cer of the GM1 molecule are tilted by ca. 55 degrees with respect to the surface normal. The plane of the beta 1,4-GalNAc sugar ring is inclined by 70 degrees towards the gold surface. The phase transition to the liquid condensed state causes simultaneous reduction (by similar to 10 degrees) of the tilt of planes of sugar residues. The plane of the alpha 2,3-Nue5Ac residue (sialic acid) has a nearly perpendicular orientation to the gold surface. Upon the transition to the liquid condensed state the strength of hydrogen bonds formed by the carboxylate group in the alpha 2,3-Nue5Ac residue decreases. In parallel, the strength of hydrogen bonds formed by N atoms of amide groups of the GM1 molecule increases. These events may be explained by loosening and/or breaking of hydrogen bonds between the carboxylate and hydroxyl groups in the alpha 2,3-Nue5Ac residue in a densely packed monolayer, due to steric hindrances. The ceramide group coupling the polar head group with the hydrophobic hydrocarbon chains, forms strong hydrogen bonds. The C=O bond of the amide group is almost perpendicular to the gold surface orientation. The hydrocarbon chains of the GM1 exist in a liquid disordered state and their physical state and orientation are not affected by the phase transition.},
      Url = {http://dx.doi.org/10.1039/b910479h} }
  • H. Wang, W. Yim, T. Klüner, und J. O. Metzger, "ESI-MS Studies and Calculations on Alkali-Metal Adduct Ions of Ruthenium Olefin Metathesis Catalysts and Their Catalytic Activity in Metathesis Reactions," Chem. Eur. J., vol. 15, iss. 41, pp. 10948-10959, 2009.
    @Article{Wang2009, Title = {ESI-MS Studies and Calculations on Alkali-Metal Adduct Ions of Ruthenium Olefin Metathesis Catalysts and Their Catalytic Activity in Metathesis Reactions},
      Author = {Wang, Hao-Yang and Yim, Wai-Leung and Klüner, Thorsten and Metzger, Jürgen O.},
      Journal = {Chem. Eur. J.},
      Pages = {10948--10959},
      Volume = {15},
      Year = {2009},
      Number = {41},
      Abstract = {Electrospray ionization mass spectrometry (ESIMS) and subsequent tandem mass spectrometry (MS/MS) analyses were used to study some important metathesis reactions with the first-generation ruthenium catalyst 1, focusing on the ruthenium complex intermediates in the catalytic cycle. In situ cationization with alkali cations (Li(+), Na(+). K(+), and Cs(+)) using a microreactor coupled directly to the ESI ion source allowed mass spectrometric detection and characterization of the ruthenium species present in solution and particularly the catalytically active monophosphine-ruthenium intermediates present in equilibrium with the respective bisphosphine-ruthenium species in solution. Moreover, the intrinsic catalytic activity of the cationized monophosphine-ruthenium complex 1a center dot K(+) was directly demonstrated by gas-phase reactions with 1-butene or ethene to give the propylidene Ru species 3a center dot K(+) and the methylidene Ru species 4a center dot K(+), respectively. Ring-closing metathesis (RCM) reactions of 1,6-heptadiene (5), 1,7-octadiene (6) and 1,8-nonadiene (7) were studied in the presence of KCl and the ruthenium alkylidene intermediates 8, 9, and 10, respectively, were detected as cationized monophosphine and bisphosphine ruthenium complexes. Acyclic diene metathesis (ADMET) polymerization of 1,9-decadiene (14) and ring-opening metathesis polymerization (ROMP) of cyclooctene (18) were studied analogously, and the expected ruthenium alkylidene intermediates were directly intercepted from reaction solution and characterized unambiguously by their isotopic patterns and ESIMS/MS. ADMET polymerization was not observed for 1,5-hexadiene (22), but the formation of the intramolecularly stabilized monophosphine ruthenium complex 23a was seen. The ratio of the signal intensities of the respective with potassium cationized monophosphine and bisphosphine alkylidene Ru species varied from [I(4a)]/[I(4)]=0.02 to [I(23a)]/[I(23)] = 10.2 and proved to be a sensitive and quantitative probe for intramolecular pi-complex formation of the monophosphine-ruthenium species and of double bonds in the alkylidene chain. MS/MS spectra revealed the intrinsic metathesis catalytic activity of the potassium adduct ions of the ruthenium alkylidene intermediates 8a, 9a, 10 a, 15 a, and 19 a. but not 23 a by elimination of the respective cycloalkene in the second step of RCM. Computations were performed to provide information about the structures of the alkali metal adduct ions of catalyst 1 and the influence of the alkali metal ions on the energy profile in the catalytic cycle of the metathesis reaction.},
      Url = {http://dx.doi.org/10.1002/chem.200900565} }
  • T. Jung, R. Beckhaus, T. Klüner, S. Höfener, und W. Klopper, "Unexpected Trimerization of Pyrazine in the Coordination Sphere of Low-Valent Titanocene Fragments," J. Chem. Theory Comput., vol. 5, iss. 8, pp. 2044-2049, 2009.
    @Article{Jung2009, Title = {Unexpected Trimerization of Pyrazine in the Coordination Sphere of Low-Valent Titanocene Fragments},
      Author = {Jung, Thomas and Beckhaus, Rüdiger and Klüner, Thorsten and Höfener, Sebastian and Klopper, Wim},
      Journal = {J. Chem. Theory Comput.},
      Pages = {2044--2049},
      Volume = {5},
      Year = {2009},
      Month = aug, Number = {8},
      Abstract = {The titanium mediated trimerization of pyrazine leads to the formation of a tris-chelate complex employing a 4a,4b,8a,8b,12a,12b-hexahydrodiyprazino(2,3-f:2',3'-h]quinoxaline ligand (HATH(6), 3). The driving force in the formation of the (CP*(2)Ti)(3)(HATH(6)) complex 2 is attributed to the formation of six Ti-N bonds. We show that density functional theory (DFT) fails to predict quantitatively correct results. Therefore, post-Hartree-Fock methods, such as second-order Moller-Plesset perturbation theory (MP2), in combination with coupled-cluster (CC) methods must be used. Both MP2 and CCSD(T) levels of theory provide endothermic trimerization energies, showing that the plain pyrazine trimer is not stable with respect to decomposition into its monomers. Complete basis set (CBS) results for the MP2 level of theory were computed using explicitly correlated wave functions. With these, we estimate the CCSD(T) CBS limit of the hypothetical trimerization energy to be +0.78 eV. Thus, the trimerization is facilitated by the formation of six Ti-N bonds with a calculated formation energy of -1.32 eV per bond.},
      Url = {http://dx.doi.org/10.1021/ct900137r} }
  • I. Mehdaoui und T. Klüner, "New mechanistic insight into electronically excited CO-NiO(100): a quantum dynamical analysis," Phys. Chem. Chem. Phys., vol. 10, iss. 31, pp. 4559-4564, 2008.
    @Article{Mehdaoui2008, Title = {New mechanistic insight into electronically excited CO-NiO(100): a quantum dynamical analysis},
      Author = {Mehdaoui, Imed and Klüner, Thorsten},
      Journal = {Phys. Chem. Chem. Phys.},
      Pages = {4559--4564},
      Volume = {10},
      Year = {2008},
      Number = {31},
      Abstract = {In a recent study Redlich et al. [Redlich et al., Chem. Phys. Lett. 2006, 420, 110] measured the velocity distribution of CO molecules desorbing from a NiO(100) surface after irradiation with an ultraviolet (UV) laser pulse. Due to the complexity of the involved processes no experimental evidence on the excitation and desorption mechanism could be obtained. In recent ab initio studies Mehdaoui et al. [Mehdaoui et al., Phys. Rev. Lett. 2007, 98, 037601] have shown that a 5 sigma - 2 pi (a 3 P) like transition within the CO adsorbate is most likely the crucial excitation step in the CO - NiO(100) system. At first sight this seems unlikely, since the interaction of CO molecules with the NiO(100) surface is very weak (-0.30 eV) and the corresponding CO gas phase transition energy is about 1.5 eV higher than the laser pulse energy of 4.66 eV used in the experiment. In this work we give further insight into relevant electronically excited states and identify the desorption mechanism by analysing the dynamical processes after laser excitation by quantum dynamical wave packet simulations on the basis of three-dimensional (3D) ab initio potential energy surfaces. The results corroborate the so far discussed excitation mechanism, which proposes the formation of a genuine C-Ni bond as the driving force for photodesorption, as the crucial excitation step.},
      Url = {http://dx.doi.org/10.1039/b805597a} }
  • W. Yim und T. Klüner, "Atoms-in-molecules analysis for planewave DFT calculations - A numerical approach on a successively interpolated charge density grid," J. Comput. Chem., vol. 29, iss. 8, pp. 1306-1315, 2008.
    @Article{Yim2008, Title = {Atoms-in-molecules analysis for planewave DFT calculations - A numerical approach on a successively interpolated charge density grid},
      Author = {Yim, Wai-Leung and Klüner, Thorsten},
      Journal = {J. Comput. Chem.},
      Pages = {1306--1315},
      Volume = {29},
      Year = {2008},
      Month = jun, Number = {8},
      Abstract = {We used a successive charge interpolation scheme and Ridders, method for differentiation, to acquire accurate charge densities and their higher derivatives in electronic structure calculations. This enables us to search bond critical points using arbitrary charge density grids. We applied the planewave-DFT code, VASP, to generate the charge density of selected benchmark molecules. The properties of bond critical points are in good agreement with those obtained by complementary implementations. We validated our GRID implementation by performing electronic structure calculations using the Gaussian 03 program package and various tools for analysis of the charge density provided by the AIMPAC package. In particular, we carefully investigate the influence of effective core potentials on the location of bond critical points, especially for a short chemical bond, which is crucial in the present pseudopotential-based planewave DFT calculations. We expect our generic implementation will not only be useful for the analysis of chemical bonding in molecules, but will particularly provide a microscopic understanding of extended systems including periodic boundary conditions. (C) 2008 Wiley Periodicals, Inc.},
      Url = {http://dx.doi.org/10.1002/jcc.20889} }
  • W. Yim und T. Klüner, "Promoting O$_2$ activation on noble metal surfaces," J. Catal., vol. 254, iss. 2, pp. 349-354, 2008.
    @Article{Yim2008a, Title = {Promoting O$_2$ activation on noble metal surfaces},
      Author = {Yim, Wai-Leung and Klüner, Thorsten},
      Journal = {J. Catal.},
      Pages = {349--354},
      Volume = {254},
      Year = {2008},
      Month = mar, Number = {2},
      Abstract = {We established a chemical modification strategy to search for a substitute of platinum toward O-2 activation. Achieving this required an understanding of the chemical bonding interactions along the corresponding reaction pathway. Using recently developed chemical bonding analysis schemes, we found that the transition state of O-2 dissociation on Pt(111) is stabilized by electrostatic interactions and the bonding interaction between the two oxygen atoms. This paves the way for tuning the O-2 activation barrier by replacing a surface atom with a less electronegative transition metal atom. We considered substituted Pd(111), Ag(111), and Au(111) surfaces and suggest some potential candidates for further screening by experimentalists. (C) 2008 Elsevier Inc. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.jcat.2008.01.018} }
  • W. Yim und T. Klüner, "Role of Electrostatic Interactions on Engineering Reaction Barriers: The Case of CO Dissociation on Supported Cobalt Particles," J. Chem. Theory Comput., vol. 4, iss. 10, pp. 1709-1717, 2008.
    @Article{Yim2008b, Title = {Role of Electrostatic Interactions on Engineering Reaction Barriers: The Case of CO Dissociation on Supported Cobalt Particles},
      Author = {Yim, Wai-Leung and Klüner, Thorsten},
      Journal = {J. Chem. Theory Comput.},
      Pages = {1709--1717},
      Volume = {4},
      Year = {2008},
      Month = oct, Number = {10},
      Abstract = {We demonstrate a systematic optimization of the activation barrier of CO dissociation on cobalt surfaces on the basis of a chemical bonding picture of the corresponding transition structures. In particular, Co clusters adsorbed on MgO(100), graphene, and carbon nanotubes have been investigated. We discovered that the C-O moiety has a polar covalent character at the transition state which is feasibly stabilized by electrostatic interactions. This can be realized by replacing the beta-Co atom with a less electronegative transition metal atom. The effect of 13 different substituting elements on CO dissociation has been investigated.},
      Url = {http://dx.doi.org/10.1021/ct800243y} }
  • [article] bibtex
    T. Klüner, "Licht steuert ultraschnelle Nanoschalter," Reinraumtechnik, vol. 9, p. 7, 2007.
    @Article{Kluener2007, Title = {Licht steuert ultraschnelle Nanoschalter},
      Author = {Klüner, Thorsten},
      Journal = {Reinraumtechnik},
      Pages = {7},
      Volume = {9},
      Year = {2007} }
  • D. Fenske, W. Yim, S. Neuendorf, D. Hoogestraat, D. Greshnykh, H. Borchert, T. Klüner, und K. Al-Shamery, "Pitfalls in interpreting temperature programmed desorption spectra of alloys: The CO/CoPt puzzle," ChemPhysChem, vol. 8, iss. 5, pp. 654-656, 2007.
    @Article{Fenske2007, Title = {Pitfalls in interpreting temperature programmed desorption spectra of alloys: The CO/CoPt puzzle},
      Author = {Fenske, Daniela and Yim, Wai-Leung and Neuendorf, Stephanie and Hoogestraat, Dirk and Greshnykh, Denis and Borchert, Holger and Klüner, Thorsten and Al-Shamery, Katharina},
      Journal = {ChemPhysChem},
      Pages = {654--656},
      Volume = {8},
      Year = {2007},
      Month = apr, Number = {5},
      Url = {http://dx.doi.org/10.1002/cphc.200700004} }
  • S. Dittrich und T. Klüner, "Calculation of thermal effects in the photodesorption of NO from NiO(100)," Appl. Phys. A, vol. 88, iss. 3, pp. 571-577, 2007.
    @Article{Dittrich2007, Title = {Calculation of thermal effects in the photodesorption of NO from NiO(100)},
      Author = {Dittrich, S. and Klüner, T.},
      Journal = {Appl. Phys. A},
      Pages = {571--577},
      Volume = {88},
      Year = {2007},
      Month = aug, Number = {3},
      Abstract = {The influence of temperature in the photodesorption of NO from a NiO(100)-surface is studied with a two-dimensional quantum wave packet approach. The complete process including laser-induced excitation and subsequent relaxation is treated explicitly from first principles. The electronic quenching caused by the interaction of the excited adsorbate-substrate system with electron-hole-pairs in the surface is treated with the surrogate Hamiltonian approach. We have implemented a parallelization scheme of the wave packet propagation based on a one-dimensional data decomposition to perform simulations in a reasonable computing time. The results are compared with mixed quantum-classical simulations and with experimental measurements. Both desorption yield and mean velocity of the desorbing molecules were enhanced with increasing temperature. The calculated rotational temperatures are consistent with experimental results.},
      Url = {http://dx.doi.org/10.1007/s00339-007-4055-0} }
  • D. Lahav und T. Klüner, "A self-consistent density based embedding scheme applied to the adsorption of CO on Pd(111)," J. Phys. Condens. Matter, vol. 19, iss. 22, p. 226001, 2007.
    @Article{Lahav2007, Title = {A self-consistent density based embedding scheme applied to the adsorption of CO on Pd(111)},
      Author = {Lahav, D. and Klüner, T.},
      Journal = {J. Phys. Condens. Matter},
      Pages = {226001},
      Volume = {19},
      Year = {2007},
      Month = jun, Number = {22},
      Abstract = {We derive a variant of a density based embedded cluster approach as an improvement to a recently proposed embedding theory for metallic substrates (Govind et al 1999 J. Chem. Phys. 110 7677; Klüner et al 2001 Phys. Rev. Lett. 86 5954). In this scheme, a local region in space is represented by a small cluster which is treated by accurate quantum chemical methodology. The interaction of the cluster with the infinite solid is taken into account by an effective one-electron embedding operator representing the surrounding region. We propose a self-consistent embedding scheme which resolves intrinsic problems of the former theory, in particular a violation of strict density conservation. The proposed scheme is applied to the well-known benchmark system CO/Pd(111).},
      Url = {http://dx.doi.org/10.1088/0953-8984/19/22/226001} }
  • I. Mehdaoui und T. Klüner, "Bonding of CO and NO to NiO(100): a strategy for obtaining accurate adsorption energies," J. Phys. Chem. A, vol. 111, iss. 50, pp. 13233-13237, 2007.
    @Article{Mehdaoui2007, Title = {Bonding of CO and NO to NiO(100): a strategy for obtaining accurate adsorption energies},
      Author = {Mehdaoui, Imed and Klüner, Thorsten},
      Journal = {J. Phys. Chem. A},
      Pages = {13233--13237},
      Volume = {111},
      Year = {2007},
      Month = dec, Number = {50},
      Abstract = {Ab initio studies of the bonding of CO and NO to a NiO(100) surface are presented. As has been shown by Pacchioni et al. (Pacchioni, G.; Di Valentin, C.; Dominguez-Ariza, D.; Illas, F.; Bredow, T.; Klüner, T.; Staemmler, V. J. Phys.: Condens. Matter 2004, 16, S2497), density functional theory (DFT) fails in predicting accurately the bonding of CO and NO to a NiO(100) surface. In particular, in the case of the NO-NiO(100) system, DFT gives a physically incorrect picture of the bonding. Although the second-order complete active space perturbation theory (CASPT2) method gives qualitatively correct results, still, some uncertainty exists regarding the experimentally predicted value of the adsorption energy. We show that an accurate description of the bonding in the CO-NiO(100) and NO-NiO(100) systems, in fact, represents a challenge to theory, and we will identify the origin of the underestimated bond strength by using different ab initio approaches, and cluster models of systematically increasing size.},
      Url = {http://dx.doi.org/10.1021/jp075703i} }
  • I. Mehdaoui und T. Klüner, "Understanding surface photochemistry from first principles: The case of CO-NiO(100)," Phys. Rev. Lett., vol. 98, iss. 3, p. 037601, 2007.
    @Article{Mehdaoui2007a, Title = {Understanding surface photochemistry from first principles: The case of CO-NiO(100)},
      Author = {Mehdaoui, Imed and Klüner, Thorsten},
      Journal = {Phys. Rev. Lett.},
      Pages = {037601},
      Volume = {98},
      Year = {2007},
      Month = jan, Number = {3},
      Abstract = {The excitation mechanism in the CO-NiO(100) system induced by a uv-laser pulse has been investigated from first principles. For the laser-driven process, the relevant electronically excited states are identified, and it is shown that a transition within the CO molecule is the crucial excitation step rather than substrate mediated processes. A new mechanism is proposed, in which the formation of a genuine C-Ni bond in the excited state is the driving force for photodesorption rather than electrostatic interactions, as has been found in similar systems. This results in very high velocities of CO molecules desorbing from the NiO(100) surface after electronic relaxation.},
      Url = {http://dx.doi.org/10.1103/PhysRevLett.98.037601} }
  • W. Yim, T. Nowitzki, M. Necke, H. Schnars, P. Nickut, J. Biener, M. M. Biener, V. Zielasek, K. Al-Shamery, T. Klüner, und M. Bäumer, "Universal phenomena of CO adsorption on gold surfaces with low-coordinated sites," J. Phys.Chem. C, vol. 111, iss. 1, pp. 445-451, 2007.
    @Article{Yim2007, Title = {Universal phenomena of CO adsorption on gold surfaces with low-coordinated sites},
      Author = {Yim, Wai-Leung and Nowitzki, Tobias and Necke, Mandus and Schnars, Hanno and Nickut, Patricia and Biener, Jürgen and Biener, Monika M. and Zielasek, Volkmar and Al-Shamery, Katharina and Klüner, Thorsten and Bäumer, Marcus},
      Journal = {J. Phys.Chem. C},
      Pages = {445--451},
      Volume = {111},
      Year = {2007},
      Month = jan, Number = {1},
      Abstract = {Since Au turned out to be an active catalyst for CO oxidation at low temperatures, CO adsorption on various Au surfaces has been in the scope of numerous surface science studies. Interestingly, supported particles as well as stepped and rough single-crystal surfaces exhibit very similar adsorption behavior. To elucidate the origin of these similarities, we have performed temperature-programmed desorption and infrared absorption spectroscopy for a whole range of Au surfaces from nanoparticles grown on HOPG to Au( 111) surfaces roughened by argon ion bombardment. In line with previous results, we have observed two desorption states at similar to 130-145 and similar to 170-185 K, respectively, and one infrared peak at around 2120 cm(-1) in all cases. In addition to the experiments, we have carried out theoretical studies of CO adsorption on Au( 332). The calculations show that CO desorption states above 100 K may be located at step-edges but not on terrace sites. Reducing the coordination of Au atoms further leads to successively higher binding energies with an unchanged anharmonic frequency. Therefore, we conclude that both desorption peaks belong to CO on low-coordinated Au atoms at steps and kinks. For the sputtered Au( 111) surface, scanning tunneling microscopy reveals a rough pit-and-mound morphology with a large number of such sites. In annealing experiments we observe that the loss of these sites coincides with the loss of CO adsorption capacity, corroborating our conclusions.},
      Url = {http://dx.doi.org/10.1021/jp0665729} }
  • I. Mehdaoui, D. Kroner, M. Pykavy, H. J. Freund, und T. Klüner, "Photo-induced desorption of NO from NiO(100): calculation of the four-dimensional potential energy surfaces and systematic wave packet studies," Phys. Chem. Chem. Phys., vol. 8, iss. 13, pp. 1584-1592, 2006.
    @Article{Mehdaoui2006, Title = {Photo-induced desorption of NO from NiO(100): calculation of the four-dimensional potential energy surfaces and systematic wave packet studies},
      Author = {Mehdaoui, I. and Kroner, D. and Pykavy, M. and Freund, H. J. and Klüner, T.},
      Journal = {Phys. Chem. Chem. Phys.},
      Pages = {1584--1592},
      Volume = {8},
      Year = {2006},
      Number = {13},
      Abstract = {The velocity distributions of the laser-induced desorption of NO molecules from an epitaxially grown film of NiO(100) on Ni(100) have been studied [ Mull et al., J. Chem. Phys., 1992, 96, 7108]. A pronounced bimodality of velocity distributions has been found, where the NO molecules desorbing with higher velocities exhibit a coupling to the rotational quantum states J. In this article we present simulations of state resolved velocity distributions on a full ab initio level. As a basis for this quantum mechanical treatment a 4D potential energy surface (PES) was constructed for the electronic ground and a representative excited state, using a NiO5Mg1318+ cluster. The PESs of the electronic ground and an excited state were calculated at the CASPT2 and the configuration interaction (CI) level of theory, respectively. Multi-dimensional quantum wave packet simulations on these two surfaces were performed for different sets of degrees of freedom. Our key finding is that at least a 3D wave packet simulation, in which the desorption coordinate Z, polar angle theta and lateral coordinate X are included, is necessary to allow the simulation of experimental velocity distributions. Analysis of the wave packet dynamics demonstrates that essentially the lateral coordinate, which was neglected in previous studies [Klüner et al., Phys. Rev. Lett. 1998, 80, 5208], is responsible for the experimentally observed bimodality. An extensive analysis shows that the bimodality is due to a bifurcation of the wave packet on the excited state PES, where the motion of the molecule parallel to the surface plays a decisive role.},
      Url = {http://dx.doi.org/10.1039/b512778e} }
  • S. Dittrich und T. Klüner, "The role of laser pulse duration in the photodesorption of NO/NiO(100)," Chem. Phys. Lett., vol. 430, iss. 4-6, pp. 443-447, 2006.
    @Article{Dittrich2006, Title = {The role of laser pulse duration in the photodesorption of NO/NiO(100)},
      Author = {Dittrich, Sören and Klüner, Thorsten},
      Journal = {Chem. Phys. Lett.},
      Pages = {443--447},
      Volume = {430},
      Year = {2006},
      Month = oct, Number = {4-6},
      Abstract = {The influence of the duration of the stimulating laser pulse in the photodesorption of NO from a NiO(100)-surface is studied theoretically within a two-dimensional quantum wave packet approach. The complete event including laser-induced excitation and subsequent electronic relaxation is treated consistently from first principles within the surrogate Hamiltonian approach for open quantum systems. We demonstrate that the common assumption of time-scale separation of excitation and relaxation does not hold if ultrashort femtosecond laser pulses are used. We predict a significant effect on rotational distributions of desorbing molecules if the time scales of electronic excitation and relaxation are similar. (c) 2006 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.cplett.2006.09.017} }
  • S. Dittrich, H. J. Freund, C. P. Koch, R. Kosloff, und T. Klüner, "Two-dimensional surrogate Hamiltonian investigation of laser-induced desorption of NO/NiO(100)," J. Chem. Phys., vol. 124, iss. 2, p. 024702, 2006.
    @Article{Dittrich2006a, Title = {Two-dimensional surrogate Hamiltonian investigation of laser-induced desorption of NO/NiO(100)},
      Author = {Dittrich, S. and Freund, H. J. and Koch, C. P. and Kosloff, R. and Klüner, T.},
      Journal = {J. Chem. Phys.},
      Pages = {024702},
      Volume = {124},
      Year = {2006},
      Month = jan, Number = {2},
      Abstract = {The photodesorption of NO from NiO(100) is studied from first principles, with electronic relaxation treated by the use of the surrogate Hamiltonian approach. Two nuclear degrees of freedom of the adsorbate-substrate system are taken into account. To perform the quantum dynamical wave-packet calculations, a massively parallel implementation with a one-dimensional data decomposition had to be introduced. The calculated desorption probabilities and velocity distributions are in qualitative agreement with experimental data. The results are compared to those of stochastic wave-packet calculations where a sufficiently large number of quantum trajectories is propagated within a jumping wave-packet scenario. (c) 2006 American Institute of Physics.},
      Url = {http://dx.doi.org/10.1063/1.2140697} }
  • T. Klüner, "Laser-induced desorption of small molecules from oxide surfaces: A first-principles study," Isr. J. Chem., vol. 45, iss. 1-2, pp. 77-95, 2005.
    @Article{Kluener2005, Title = {Laser-induced desorption of small molecules from oxide surfaces: A first-principles study},
      Author = {Klüner, T.},
      Journal = {Isr. J. Chem.},
      Pages = {77--95},
      Volume = {45},
      Year = {2005},
      Number = {1-2},
      Abstract = {Recent efforts in the theoretical simulation of laser-induced desorption of small molecules from surfaces are summarized. As a representative example, photodesorption of CO molecules from a Cr2O3(0001) surface is investigated since detailed quantum state resolved experimental results are available for this system. In particular, vectorial properties such as the alignment of the desorbing species are considered. Furthermore, the influence of surface temperature as a control parameter is investigated, and lateral velocity distributions are calculated and compared with experimental results. All simulations presented in the present study are based on ab initio potential energy surfaces (PESs) for the electronic ground state as well as electronically excited states involved in the desorption process. These PESs provide the prerequisite for extensive high-dimensional quantum mechanical simulations of the dynamics of nuclear motion based on a stochastic wave packet scheme. These wave packet calculations allow for a detailed microscopic understanding of experimental results and provide a perspective for future experiments.},
      Url = {http://dx.doi.org/10.1560/M26E-39HX-PL8K-NBVU} }
  • A. Cörper, G. Bozdech, N. Ernst, T. Klüner, und H. J. Freund, "Field electron energy spectroscopy of alumina-supported platinum adatoms," Phys. Status Solidi, vol. 242, iss. 12, pp. 2462-2467, 2005.
    @Article{Coerper2005, Title = {Field electron energy spectroscopy of alumina-supported platinum adatoms},
      Author = {Cörper, A. and Bozdech, G. and Ernst, N. and Klüner, T. and Freund, H. J.},
      Journal = {Phys. Status Solidi},
      Pages = {2462--2467},
      Volume = {242},
      Year = {2005},
      Month = oct, Number = {12},
      Abstract = {Field electron energy spectroscopy and density functional calculations have been employed to characterize electronic properties of single Pt-adatoms deposited on a thin alumina film. For Pt/Al2O3/NiAl(110) strong current enhancements were measured about 1.4 eV below the Fermi energy. No features were observed for clean Al2O3/NiAl(110) and Pt/NiAl(110) in the accessible energy range. As an explanation we propose a resonance tunneling mechanism involving an occupied electronic state of the Pt adatom close to the Fermi level. (c) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.},
      Url = {http://dx.doi.org/10.1002/pssb.200450088} }
  • D. Kröner, I. Mehdaoui, H. J. Freund, und T. Klüner, "Three-dimensional ab initio simulation of laser-induced desorption of NO from NiO(100)," Chem. Phys. Lett., vol. 415, iss. 1-3, pp. 150-154, 2005.
    @Article{Kroener2005, Title = {Three-dimensional ab initio simulation of laser-induced desorption of NO from NiO(100)},
      Author = {Kröner, D. and Mehdaoui, I. and Freund, H. J. and Klüner, T.},
      Journal = {Chem. Phys. Lett.},
      Pages = {150--154},
      Volume = {415},
      Year = {2005},
      Month = oct, Number = {1-3},
      Abstract = {Laser-induced desorption of NO molecules from a NiO(100) surface is studied on an ab initio level. Based on ab initio NiO-cluster calculations a three-dimensional potential energy surface was constructed for the electronic ground and a representative excited state. Quantum wave packet calculations on these surfaces allow the simulation of experimental velocity distributions of the desorbed NO molecules. Analysis of the wave packet dynamics demonstrates that the experimentally observed bimodality of the velocity distributions is caused by a bifurcation of the wave packet on the excited state potential, where the molecular motion parallel to the surface plays a decisive role. (c) 2005 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.cplett.2005.08.124} }
  • R. Meyer, D. Lahav, T. Schalow, M. Laurin, B. Brandt, S. Schauermann, S. Guimond, T. Klüner, H. Kuhlenbeck, J. Libuda, S. Shaikhutdinov, und H. J. Freund, "CO adsorption and thermal stability of Pd deposited on a thin FeO(111) film," Surf. Sci., vol. 586, iss. 1-3, pp. 174-182, 2005.
    @Article{Meyer2005, Title = {CO adsorption and thermal stability of Pd deposited on a thin FeO(111) film},
      Author = {Meyer, R. and Lahav, D. and Schalow, T. and Laurin, M. and Brandt, B. and Schauermann, S. and Guimond, S. and Klüner, T. and Kuhlenbeck, H. and Libuda, J. and Shaikhutdinov, S. and Freund, H. J.},
      Journal = {Surf. Sci.},
      Pages = {174--182},
      Volume = {586},
      Year = {2005},
      Month = jul, Number = {1-3},
      Abstract = {We have studied adsorption of CO on Pd deposited on a thin FeO(111) film grown on a Pt(111) substrate using temperature programmed desorption, infrared reflection absorption spectroscopy and molecular beam techniques. At sub-monolayer Pd coverage, where formation of Pd(I 11) single layer islands upon heating is suggested on the basis of scanning tunneling microscopy studies, the CO desorption temperature is 70-100 K lower than on a Pd(1 11) single crystal, which agrees well with the results of ab initio calculations. However, annealing to 600 K results in strong reduction of the CO adsorption capacity, which is rationalized in terms of significant Pd migration through the film as revealed by angular resolved photoelectron spectroscopy measurements using synchrotron radiation. The results demonstrate the complexity of Pd interaction with the thin FeO(l 11) film at elevated temperatures. (c) 2005 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.susc.2005.05.011} }
  • M. Morkel, H. Unterhalt, T. Klüner, G. Rupprechter, und H. J. Freund, "Interpreting intensities in vibrational sum frequency generation (SFG) spectroscopy: CO adsorption on Pd surfaces," Surf. Sci., vol. 586, iss. 1-3, pp. 146-156, 2005.
    @Article{Morkel2005, Title = {Interpreting intensities in vibrational sum frequency generation (SFG) spectroscopy: CO adsorption on Pd surfaces},
      Author = {Morkel, M. and Unterhalt, H. and Klüner, T. and Rupprechter, G. and Freund, H. J.},
      Journal = {Surf. Sci.},
      Pages = {146--156},
      Volume = {586},
      Year = {2005},
      Month = jul, Number = {1-3},
      Abstract = {The lineshape and intensity of SFG signals of CO adsorbed on supported Pd nanoparticles and Pd(I 1 1) are analyzed. For CO/Pd(111) nearly symmetric lorentzian lineshapes were observed. Applying two different visible wavelengths for excitation, asymmetric lineshapes observed for the CO/Pd/Al-2/O-3/NiAl(110) system are explained by a lower resonant and a higher non-resonant SFG signal and a change in the phase between resonant and non-resonant signals, most likely originating from an interband transition in the NiAl substrate. The relative intensity of different CO species (hollow, bridge, on-top) was modeled by DFT calculations of IR transition moments and Raman activities. While the (experimental) sensitivity of SFG towards different CO species strongly varies, the calculated IR and Raman activities are rather similar. The inability to exactly reproduce experimental SFG intensities suggests a strong coverage dependence of Raman activities or that non-linear effects occur that can currently not be properly accounted for. (c) 2005 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.susc.2005.05.009} }
  • D. E. Starr, F. M. T. Mendes, J. Middeke, R. -P. Blum, H. Niehus, D. Lahav, S. Guimond, A. Uhl, T. Klüner, M. Schmal, H. Kuhlenbeck, S. Shaikhutdinov, und H. -J. Freund, "Preparation and characterization of well-ordered, thin niobia films on a metal substrate.," Surf. Sci., vol. 599, iss. 1-3, pp. 14-26, 2005.
    @Article{Starr2005, Title = {Preparation and characterization of well-ordered, thin niobia films on a metal substrate.},
      Author = {Starr, D. E. and Mendes, F. M. T. and Middeke, J. and Blum, R.-P. and Niehus, H. and Lahav, D. and Guimond, S. and Uhl, A. and Klüner, T. and Schmal, M. and Kuhlenbeck, H. and Shaikhutdinov, S. and Freund, H.-J.},
      Journal = {Surf. Sci.},
      Pages = {14--26},
      Volume = {599},
      Year = {2005},
      Number = {1-3},
      Abstract = {Combining LEED, scanning tunneling microscopy, angular resolved photoelectron spectroscopy using synchrotron radiation and d. functional theory calcns., we have studied the structure of thin niobia films grown on a Cu3Au(1 0 0) substrate. Nb deposition onto oxygen implanted Cu3Au(1 0 0) and subsequent oxidn. results in a flat, well-ordered thin niobia film of hexagonal symmetry. The results suggest that the film consists of 2/3 ML of Nb between two hexagonal O-layers, where Nb5+ cations occupy the threefold hollow sites. This leads to a ( 3 × 3 ) R30° structure with respect to the underlying close packed O layer, which in turn forms a (2 × 7) coincidence structure with the metal substrate. The defect structure includes reflection domain boundaries and vacancies. [on SciFinder(R)]},
      ISSN = {0039-6028},
      Keywords = {growth surface structure niobia film copper gold},
      Publisher = {Elsevier B.V.},
      Url = {http://dx.doi.org/10.1016/j.susc.2005.09.033} }
  • [article] bibtex
    T. Klüner und G. Rauhut, "Trendbericht Theoretische Chemie 2003," Nachr. Chem., vol. 52, iss. 3, pp. 313-316, 2004.
    @Article{Kluener2004, Title = {Trendbericht Theoretische Chemie 2003},
      Author = {Klüner, T. and Rauhut, G.},
      Journal = {Nachr. Chem.},
      Pages = {313--316},
      Volume = {52},
      Year = {2004},
      Month = mar, Number = {3} }
  • C. Bach, T. Klüner, und A. Groß, "Multi-dimensional mixed quantum-classical description of the laser-induced desorption of molecules," Appl. Phys. A, vol. 78, iss. 2, pp. 231-238, 2004.
    @Article{Bach2004, Title = {Multi-dimensional mixed quantum-classical description of the laser-induced desorption of molecules},
      Author = {Bach, C. and Klüner, T. and Groß, A.},
      Journal = {Appl. Phys. A},
      Pages = {231--238},
      Volume = {78},
      Year = {2004},
      Number = {2},
      Abstract = {A mixed quantum-classical method for the simulation of laser-induced desorption processes at surfaces is implemented. In this method, the nuclear motion is described classically, while the electrons are treated quantum mech. The feedback between nuclei and electrons is taken into account self-consistently. The computational efficiency of this method allows a more realistic multi-dimensional treatment of desorption processes. We apply this method to the laser-induced desorption of NO from NiO(100) using a 2-state 2D potential energy surface derived from ab initio quantum chem. calcns.; we extend this potential energy surface to seven dimensions employing a phys. reasonable model potential. By comparing our method to jumping wave-packet calcns. on exactly the same potential energy surface we verify the validity of our method. We focus on the velocity, rotational, and vibrational distributions of the desorbing NO mols. Furthermore, we model the energy transfer to the substrate by a surface oscillator. Including recoil processes in the simulation has a decisive influence on the desorption dynamics, as far as the velocity and rotational distribution is concerned. In particular, the bimodality in the velocity distribution obsd. in low dimensions and in the expt. disappears in a high-dimensional treatment. [on SciFinder(R)]},
      Url = {http://dx.doi.org/10.1007/s00339-003-2307-1} }
  • G. Pacchioni, C. Di Valentin, D. Dominguez-Ariza, F. Illas, T. Bredow, T. Klüner, und V. Staemmler, "Bonding of NH$_3$, CO, and NO to NiO and Ni-doped MgO: A problem for density functional theory.," J. Phys.: Condens. Matter, vol. 16, iss. 26, p. s2497-s2507, 2004.
    @Article{Pacchioni2004, Title = {Bonding of NH$_3$, CO, and NO to NiO and Ni-doped MgO: A problem for density functional theory.},
      Author = {Pacchioni, Gianfranco and Di Valentin, Cristiana and Dominguez-Ariza, David and Illas, Francesc and Bredow, Thomas and Klüner, Thorsten and Staemmler, Volker.},
      Journal = {J. Phys.: Condens. Matter},
      Pages = {S2497-S2507--},
      Volume = {16},
      Year = {2004},
      Number = {26},
      Abstract = {Recent exptl. results (Höft et al 2001 Phys. Rev. Lett. 87 086101) have questioned the capability of current theor. methods for describing the bonding of NH3, CO, and NO with the NiO(100) surface. We show that these systems do indeed represent a challenge to theory. For different reasons, d. functional theory (DFT) fails in describing the bonding of these mols. to the NiO surface. The gradient-cor. functionals which work better for the properties of NH3/NiO and CO/NiO (energies, geometries, vibrations) provide wrong answers for NO/NiO and vice versa. This is not due to the well-known difficulty as regards DFT describing the insulating character of NiO. In fact, exactly the same problem is found for isolated Ni2+ impurities in MgO. A correct description of the bonding of both closed-shell (NH3 and CO) and open-shell (NO) mols. to NixMg1-xO is obtained only after inclusion of dynamical correlation and dispersion forces via wavefunction-based methods. However, even with correlated calcns. some uncertainties exist regarding the predicted value of the energy of adsorption of NO on NiO. While CASPT2 calcns. reach reasonable agreement with expt., the results of approx. coupled-cluster calcns. (the multi-configuration coupled-electron-pair approach) substantially underestimate the adsorption energy. [on SciFinder(R)]},
      Url = {http://dx.doi.org/10.1088/0953-8984/16/26/024} }
  • S. Borowski, T. Klüner, H. J. Freund, I. Klinkmann, K. Al-Shamery, M. Pykavy, und V. Staemmler, "Lateral velocity distributions in laser-induced desorption of CO from Cr2O3(0001): experiment and theory," Appl. Phys. A, vol. 78, iss. 2, pp. 223-230, 2004.
    @Article{Borowski2004, Title = {Lateral velocity distributions in laser-induced desorption of CO from Cr2O3(0001): experiment and theory},
      Author = {Borowski, S. and Klüner, T. and Freund, H. J. and Klinkmann, I. and Al-Shamery, K. and Pykavy, M. and Staemmler, V.},
      Journal = {Appl. Phys. A},
      Pages = {223--230},
      Volume = {78},
      Year = {2004},
      Month = jan, Number = {2},
      Abstract = {Quantum state resolved determination of lateral velocity distributions in laser-induced desorption of CO from a Cr2O3(0001) surface is investigated. Experimentally, Doppler profiles are obtained via a (1+1('))-REMPI detection scheme for various rovibrational states and desorption velocities. The experimental findings are directly compared to theoretical results from high-dimensional stochastic quantum dynamical wave packet calculations based on complete first-principles potential energy surfaces. Reasonable quantitative agreement between experiment and theory concerning the total width as well as the full width at half maximum of the lateral velocity distributions is found. Depending on the rotational state a single-peaked or a double-peaked shape of the Doppler profiles is predicted theoretically. In order to support our theoretical predictions we suggest refined experimental investigations of the state-resolved Doppler profiles with an enhanced signal to noise ratio and further theoretical studies concerning the nature of the electronically excited intermediate.},
      Url = {http://dx.doi.org/10.1007/s00339-003-2306-2} }
  • S. Borowski und T. Klüner, "Massively parallel Hamiltonian action in pseudospectral algorithms applied to quantum dynamics of laser induced desorption," Chem. Phys., vol. 304, iss. 1-2, pp. 51-58, 2004.
    @Article{Borowski2004a, Title = {Massively parallel Hamiltonian action in pseudospectral algorithms applied to quantum dynamics of laser induced desorption},
      Author = {Borowski, S. and Klüner, T.},
      Journal = {Chem. Phys.},
      Pages = {51--58},
      Volume = {304},
      Year = {2004},
      Month = sep, Number = {1-2},
      Abstract = {The Hamiltonian action upon a wavefunction is the basic operation in iterative propagation schemes. Aiming at high-dimensional quantum dynamics, we introduce a parallel algorithm for a Hamiltonian action utilizing pseudospectral schemes on multidimensional grids. This algorithm is exemplified for a six-dimensional (6D) quantum dynamical system described in Fourier coordinates. The performance outcome of our parallel implementation is revealed by an almost linear overall scaled speedup that is only limited by present hardware resources. Our parallelization strategy is realized in ab initio four-dimensional (4D) quantum dynamical studies investigating the lateral dynamics of CO photodesorbing from a Cr(2)O(3)(0 0 0 1) surface. (C) 2004 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.chemphys.2004.06.012} }
  • C. Bach, T. Klüner, und A. Groß, "Simulation of laser-induced desorption of NO from NiO(100)," Chem. Phys. Lett., vol. 376, iss. 3-4, pp. 424-431, 2003.
    @Article{Bach2003, Title = {Simulation of laser-induced desorption of NO from NiO(100)},
      Author = {Bach, C. and Klüner, T. and Groß, A.},
      Journal = {Chem. Phys. Lett.},
      Pages = {424--431},
      Volume = {376},
      Year = {2003},
      Month = jul, Number = {3-4},
      Abstract = {We have implemented a mixed quantum-classical scheme for the simulation of the laser-induced desorption from surfaces. This method allows a multidimensional simulation of the desorption process on realistic time scales. Using ab initio derived potential energy surfaces, we compare the mixed quantum-classical scheme to jumping wave-packet calculations for the laser-induced desorption of NO from NiO(l 0 0). Our results demonstrate the significant role of the multidimensionality in the desorption process, in particular the importance of surface recoil processes. (C) 2003 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/S0009-2614(03)01023-6} }
  • S. Borowski, T. Klüner, und H. J. Freund, "Complete analysis of the angular momentum distribution of molecules desorbing from a surface," J. Chem. Phys., vol. 119, iss. 19, pp. 10367-10375, 2003.
    @Article{Borowski2003, Title = {Complete analysis of the angular momentum distribution of molecules desorbing from a surface},
      Author = {Borowski, S. and Klüner, T. and Freund, H. J.},
      Journal = {J. Chem. Phys.},
      Pages = {10367--10375},
      Volume = {119},
      Year = {2003},
      Month = nov, Number = {19},
      Abstract = {We theoretically analyze the angular momentum distribution of molecules desorbing from a surface. The adsorbate is shown to possess the complete point symmetry of the surface if the molecules adsorb in statistically equilibrated local order. Considering the symmetry of the angular momentum distribution, this point symmetry adopted to the desorbate is particularly taken into account. From the symmetry analysis, the cancellation of several terms in the angular momentum distribution is concluded. The symmetry related sparseness of the angular momentum distribution strongly simplifies the interpretation of experimental data and thus enables an appropriate comparison between experiment and theory. The benefit of this simplified picture is demonstrated by the example of the laser induced desorption of CO molecules from a Cr2O3(0001) surface. (C) 2003 American Institute of Physics.},
      Url = {http://dx.doi.org/10.1063/1.1618212} }
  • C. P. Koch, T. Klüner, H. J. Freund, und R. Kosloff, "Surrogate Hamiltonian study of electronic relaxation in the femtosecond laser induced desorption of NO/NiO(100)," J. Chem. Phys., vol. 119, iss. 3, pp. 1750-1765, 2003.
    @Article{Koch2003, Title = {Surrogate Hamiltonian study of electronic relaxation in the femtosecond laser induced desorption of NO/NiO(100)},
      Author = {Koch, C. P. and Klüner, T. and Freund, H. J. and Kosloff, R.},
      Journal = {J. Chem. Phys.},
      Pages = {1750--1765},
      Volume = {119},
      Year = {2003},
      Month = jul, Number = {3},
      Abstract = {A microscopic model for electronic quenching in the photodesorption of NO from NiO(100) is developed. The quenching is caused by the interaction of the excited adsorbate-substrate complex with electron hole pairs (O 2p-->Ni 3d states) in the surface. The electron hole pairs are described as a bath of two level systems which are characterized by an excitation energy and a dipole charge. The parameters are connected to estimates from photoemission spectroscopy and configuration interaction calculations. Due to the localized electronic structure of NiO a direct optical excitation mechanism can be assumed, and a reliable potential energy surface for the excited state is available. Thus a treatment of all steps in the photodesorption event from first principles becomes possible for the first time. The surrogate Hamiltonian method, which allows one to monitor convergence, is employed to calculate the desorption dynamics. Desorption probabilities of the right order of magnitude and velocities in the experimentally observed range are obtained. (C) 2003 American Institute of Physics.},
      Url = {http://dx.doi.org/10.1063/1.1577533} }
  • T. Risse, A. Carlsson, M. Bäumer, T. Klüner, und H. J. Freund, "Using IR intensities as a probe for studying the surface chemical bond," Surf. Sci., vol. 546, iss. 2-3, p. l829-l835, 2003.
    @Article{Risse2003, Title = {Using IR intensities as a probe for studying the surface chemical bond},
      Author = {Risse, T. and Carlsson, A. and Bäumer, M. and Klüner, T. and Freund, H. J.},
      Journal = {Surf. Sci.},
      Pages = {L829--L835},
      Volume = {546},
      Year = {2003},
      Month = dec, Number = {2-3},
      Abstract = {Infrared (IR) intensities as determined by a combination of temperature dependent IR spectroscopy and temperature programmed desorption (TPD) were used to identify adsorption sites on Co and Co-Pd nano particles. It is shown that CO adsorption to metal atoms with a low metal coordination exhibits a strong intensity enhancement of the IR absorption as compared to regular surface sites. Density functional theory (DFT) calculations show that this intensity enhancement is due to a decoupling of the low coordinated metal atom bound to CO from those metal atoms embedded in the metal surface. (C) 2003 Elsevier B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/j.susc.2003.09.044} }
  • S. K. Shaikhutdinov, R. Meyer, D. Lahav, M. Bäumer, T. Klüner, und H. J. Freund, "Determination of atomic structure of the metal-oxide interface: Pd nanodeposits on an FeO(111) film," Phys. Rev. Lett., vol. 91, iss. 7, p. 076102, 2003.
    @Article{Shaikhutdinov2003, Title = {Determination of atomic structure of the metal-oxide interface: Pd nanodeposits on an FeO(111) film},
      Author = {Shaikhutdinov, S. K. and Meyer, R. and Lahav, D. and Bäumer, M. and Klüner, T. and Freund, H. J.},
      Journal = {Phys. Rev. Lett.},
      Pages = {076102},
      Volume = {91},
      Year = {2003},
      Month = aug, Number = {7},
      Abstract = {Palladium was vapor deposited on a thin FeO(111) film grown on a Pt(111) substrate. Scanning tunneling microscopy study has revealed that Pd wets the FeO substrate and at elevated temperatures forms extended Pd(111) monolayer islands in contrast to other oxide supports previously studied. For the first time, we have imaged the metal-oxide interface structure with atomic resolution and explained the results on the basis of ab initio calculations.},
      Url = {http://dx.doi.org/10.1103/PhysRevLett.91.076102} }
  • C. P. Koch, T. Klüner, H. J. Freund, und R. Kosloff, "Femtosecond photodesorption of small molecules from surfaces: A theoretical investigation from first principles," Phys. Rev. Lett., vol. 90, iss. 11, p. 117601, 2003.
    @Article{Koch2003a, Title = {Femtosecond photodesorption of small molecules from surfaces: A theoretical investigation from first principles},
      Author = {Koch, C. P. and Klüner, T. and Freund, H. J. and Kosloff, R.},
      Journal = {Phys. Rev. Lett.},
      Pages = {117601},
      Volume = {90},
      Year = {2003},
      Month = mar, Number = {11},
      Abstract = {A microscopic model for the excitation and relaxation processes in photochemistry at surfaces is developed. Our study is based on ab initio calculations and the surrogate Hamiltonian method treating surface electron-hole pairs as a bath of two-level systems. Desorption probabilities and velocities in the experimentally observed range are obtained. The excited state lifetime is calculated, and a dependence of observables on pulse length is predicted.},
      Url = {http://dx.doi.org/10.1103/PhysRevLett.90.117601},
      Zs = {0} }
  • T. Klüner, N. Govind, Y. A. Wang, und E. A. Carter, "Klüner \textitet al. Reply:," Phys. Rev. Lett., vol. 88, p. 209702, 2002.
    @Article{Kluener2002a, Title = {Klüner \textit{et al.} Reply:},
      Author = {Klüner, T. and Govind, N. and Wang, Y. A. and Carter, E. A.},
      Journal = {Phys. Rev. Lett.},
      Pages = {209702},
      Volume = {88},
      Year = {2002},
      Month = {May},
      Url = {http://dx.doi.org/10.1103/PhysRevLett.88.209702} }
  • S. Borowski, S. Thiel, T. Klüner, H. J. Freund, R. Tisma, und H. Lederer, "High-dimensional quantum dynamics of molecules on surfaces: a massively parallel implementation," Comput. Phys. Commun., vol. 143, iss. 2, p. pii s0010-4655(01)00445, 2002.
    @Article{Borowski2002, Title = {High-dimensional quantum dynamics of molecules on surfaces: a massively parallel implementation},
      Author = {Borowski, S. and Thiel, S. and Klüner, T. and Freund, H. J. and Tisma, R. and Lederer, H.},
      Journal = {Comput. Phys. Commun.},
      Pages = {PII S0010-4655(01)00445-3},
      Volume = {143},
      Year = {2002},
      Month = feb, Number = {2},
      Abstract = {We present a massively parallel implementation to perform quantum dynamical wave packet calculations of molecules on surfaces. The employed algorithm propagates the wavefunction via the time-dependent Schrodinger equation within a finite basis representation by Split and Chebyshev schemes, respectively. For the parallelization, a problem adapted data decomposition in all dimensions is introduced that ensures an optimal load balancing. In a speedup analysis of the timing and scaling properties, the overall semi-linear scaling of the algorithm is verified. The almost linear speedup up to 512 processing elements indicates our implementation as a powerful tool for high-dimensional calculations. The implementation is applied to laser induced desorption of molecules from surfaces. (C) 2002 Elsevier Science B.V All rights reserved.},
      Url = {http://dx.doi.org/10.1016/S0010-4655(01)00445-3} }
  • A. Delin und T. Klüner, "Excitation spectra and ground-state properties from density-functional theory for the inverted band-structure systems $\beta$-HgS, HgSe, and HgTe," Phys. Rev. B, vol. 66, iss. 3, p. 035117, 2002.
    @Article{Delin2002, Title = {Excitation spectra and ground-state properties from density-functional theory for the inverted band-structure systems $\beta$-HgS, HgSe, and HgTe},
      Author = {Delin, A. and Klüner, T.},
      Journal = {Phys. Rev. B},
      Pages = {035117},
      Volume = {66},
      Year = {2002},
      Month = jul, Number = {3},
      Abstract = {We have performed a systematic density-functional study of the mercury chalcogenide compounds beta-HgS, HgSe, and HgTe using an all-electron full-potential linear muffin-tin orbital method. We find that, in the zinc-blende structure, both HgSe and HgTe are semimetals whereas beta-HgS has a small spin-orbit-induced band gap. Our calculated relativistic photoemission and inverse photoemission spectra reproduce very well the most recently measured spectra, as do also our theoretical optical spectra. In contrast to the normal situation, we find that the local density approximation to the density functional gives calculated equilibrium volumes in much better agreement with experiment than does the generalized gradient corrected functional. We also address the problem of treating relativistic p electrons with methods based on a scalar-relativistic basis set and show that the effect is rather small for the present systems.},
      Url = {http://dx.doi.org/10.1103/PhysRevB.66.035117} }
  • T. Klüner, N. Govind, Y. A. Wang, und E. A. Carter, "Periodic density functional embedding theory for complete active space self-consistent field and configuration interaction calculations: Ground and excited states," J. Chem. Phys., vol. 116, iss. 1, pp. 42-54, 2002.
    @Article{Kluener2002, Title = {Periodic density functional embedding theory for complete active space self-consistent field and configuration interaction calculations: Ground and excited states},
      Author = {Klüner, T. and Govind, N. and Wang, Y. A. and Carter, E. A.},
      Journal = {J. Chem. Phys.},
      Pages = {42--54},
      Volume = {116},
      Year = {2002},
      Month = jan, Number = {1},
      Abstract = {We extend our recently reported embedding theory [J. Chem. Phys. 110, 7677 (1999)] to calculate not only improved descriptions of ground states, but now also localized excited states in a periodically infinite condensed phase. A local region of the solid is represented by a small cluster for which high quality quantum chemical calculations are performed. The interaction of the cluster with the extended condensed phase is taken into account by an effective embedding potential. This potential is calculated by periodic density functional theory (DFT) and is used as a one-electron operator in subsequent cluster calculations. Among a variety of benchmark calculations, we investigate a CO molecule adsorbed on a Pd(111) surface. By performing complete active space self-consistent field, configuration interaction (CI), and Moller-Plesset perturbation theory of order n (MP-n), we not only were able to obtain accurate adsorption energies via local corrections to DFT, but also vertical excitation energies for an internal (5 sigma -->2 pi*) excitation within the adsorbed CO molecule. We demonstrate that our new scheme is an efficient and accurate approach for the calculation of local excited states in bulk metals and on metal surfaces. Additionally, a systematic means of improving locally on ground state properties is provided. (C) 2002 American Institute of Physics.},
      Url = {http://dx.doi.org/10.1063/1.1420748} }
  • C. P. Koch, T. Klüner, und R. Kosloff, "A complete quantum description of an ultrafast pump-probe charge transfer event in condensed phase," J. Chem. Phys., vol. 116, iss. 18, pp. 7983-7996, 2002.
    @Article{Koch2002, Title = {A complete quantum description of an ultrafast pump-probe charge transfer event in condensed phase},
      Author = {Koch, C. P. and Klüner, T. and Kosloff, R.},
      Journal = {J. Chem. Phys.},
      Pages = {7983--7996},
      Volume = {116},
      Year = {2002},
      Month = may, Number = {18},
      Abstract = {An ultrafast photoinduced charge transfer event in condensed phase is simulated. The interaction with the field is treated explicitly within a time-dependent framework. The description of the interaction of the system with its environment is based on the surrogate Hamiltonian method where the infinite number of degrees of freedom of the environment is approximated by a finite set of two-level modes for a limited time. This method is well suited to ultrafast events, since it is not limited by weak coupling between system and environment. Moreover, the influence of the external field on the system-bath coupling is included naturally. The surrogate Hamiltonian method is generalized to incorporate two electronic states including all possible system-bath interactions. The method is applied to a description of a pump-probe experiment where every step of the cycle is treated consistently. Dynamical variables are considered which go beyond rates of charge transfer such as the transient absorption spectrum. The parameters of the model are chosen to mimic the mixed valence system (NH3)(5)RuNCRu(CN)(5)(-). (C) 2002 American Institute of Physics.},
      Url = {http://dx.doi.org/10.1063/1.1450124} }
  • M. Pykavy, S. Thiel, und T. Klüner, "Laser-induced desorption of CO from Cr$_2$O$_3$ (0001): Ab initio calculation of the four-dimensional potential energy surface for an intermediate excited state," J. Phys. Chem. B, vol. 106, iss. 48, pp. 12556-12562, 2002.
    @Article{Pykavy2002, Title = {Laser-induced desorption of CO from Cr$_2$O$_3$ (0001): Ab initio calculation of the four-dimensional potential energy surface for an intermediate excited state},
      Author = {Pykavy, M. and Thiel, S. and Klüner, T.},
      Journal = {J. Phys. Chem. B},
      Pages = {12556--12562},
      Volume = {106},
      Year = {2002},
      Month = dec, Number = {48},
      Abstract = {Ab initio cluster calculations for an excited state of the system CO/Cr2O3 (0001) are presented. A CO(a (3)Pi)-like state generated by an internal electronic excitation of the CO molecule (5sigma --> 2pi*) is considered to be a possible intermediate for the laser-induced desorption of CO from Cr2O3 (0001). A four-dimensional potential energy surface (PES) for this state is calculated at the CASSCF level of theory. A few possible alternatives for the desorption intermediate are also discussed. The interaction mechanism between the excited CO molecule and the-surface is analyzed, and it is shown that the change of symmetry of the quadrupole moment of the CO molecule is responsible for the topology of the calculated PES.},
      Url = {http://dx.doi.org/10.1021/jp026597h} }
  • S. Thiel, T. Klüner, D. Lemoine, und H. J. Freund, "Rovibrational preexcitation in the photodesorption of CO from Cr$_2$O$_3$," Chem. Phys., vol. 282, iss. 3, p. pii s0301-0104(02)00770, 2002.
    @Article{Thiel2002, Title = {Rovibrational preexcitation in the photodesorption of CO from Cr$_2$O$_3$},
      Author = {Thiel, S. and Klüner, T. and Lemoine, D. and Freund, H. J.},
      Journal = {Chem. Phys.},
      Pages = {PII S0301-0104(02)00770-X},
      Volume = {282},
      Year = {2002},
      Month = sep, Number = {3},
      Abstract = {The influence of rovibrational preexcitation in the CO/Cr2O3(0 0 0 1)-system is studied theoretically using a three-dimensional quantum wave packet approach. We find that selectively excited hindered rotational levels of the adsorbate-substrate system influence the experimentally observed rotational alignment of the desorbing CO-molecule significantly. Pure vibrational preexcitation has less effect on the observables of interest. We predict only low surface temperature dependence of the rotational alignment and of the desorption yield. Our study is based on ab initio potential energy surfaces (PESs) for the electronic states involved and on a stochastic wave packet method. (C) 2002 Elsevier Science B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/S0301-0104(02)00770-X} }
  • S. Thiel, M. Pykavy, T. Klüner, H. J. Freund, R. Kosloff, und V. Staemmler, "Rotational alignment in the photodesorption of CO from Cr$_2$O$_3$(0001): A systematic three-dimensional ab initio study," J. Chem. Phys., vol. 116, iss. 2, pp. 762-773, 2002.
    @Article{Thiel2002a, Title = {Rotational alignment in the photodesorption of CO from Cr$_2$O$_3$(0001): A systematic three-dimensional ab initio study},
      Author = {Thiel, S. and Pykavy, M. and Klüner, T. and Freund, H. J. and Kosloff, R. and Staemmler, V.},
      Journal = {J. Chem. Phys.},
      Pages = {762--773},
      Volume = {116},
      Year = {2002},
      Month = jan, Number = {2},
      Abstract = {In recent experiments, the rotational alignment of the laser induced nonthermal desorption of CO adsorbed on an epitaxially grown film of Cr2O3(0001) has been studied [Beauport, Al-Shamery, and Freund, Chem. Phys. Lett. 256, 641 (1996)]. At low-rotational quantum numbers J, the molecules desorb like helicopters (J-vector perpendicular to the surface) while at high J-values cartwheel motion is preferred (J-vector parallel to the surface). These stereodynamic effects and the experimental state resolved velocity distributions of the desorbing species are simulated by means of an exact time-dependent wave packet method in three dimensions. As a basis for this quantum-mechanical treatment of the CO desorption ab initio potential energy surfaces (PES) were used. The PES for the electronic ground state of the CO-Cr2O3(0001) system has been calculated previously by Pykavy [Surf. Sci. 479, 11 (2001)] in an embedded cluster approach. As the intermediate state, generated by the laser irradiation, an internal CO excited state (5 sigma -->2 pi*) was considered. The PES of this a (3)Pi -like state of CO adsorbed on Cr2O3(0001) was calculated at the ab initio CASSCF-level. Our key findings in the subsequent wave packet calculations are (1) a high-dimensional treatment of the photodesorption process is very important in this system, essentially the angular coordinates, very often neglected in similar studies, are responsible for a "successful" desorption event; (2) the change from the strongly tilted equilibrium geometry in the electronic ground state to the preferred upright position in the electronically excited state after laser irradiation is essential for the mechanistic picture of the desorption process; (3) the experimental phenomemon of rotational alignment can only be explained if the topologies of the PES of both the electronically excited and the ground state are accounted for; (4) the lifetime of the CO*-intermediate is in the order of 10 fs; (5) the molecule-surface vibrations in the electronic ground state do not much influence the asymptotic results at the experimental temperature of T=100 K. However, the inclusion of excited levels of the hindered rotation helps to gain insight into the desorption mechanism on a microscopic level. (C) 2002 American Institute of Physics.},
      Url = {http://dx.doi.org/10.1063/1.1425383} }
  • T. Klüner, N. Govind, Y. A. Wang, und E. A. Carter, "Prediction of electronic excited states of adsorbates on metal surfaces from first principles," Phys. Rev. Lett., vol. 86, iss. 26, pp. 5954-5957, 2001.
    @Article{Kluener2001, Title = {Prediction of electronic excited states of adsorbates on metal surfaces from first principles},
      Author = {Klüner, T. and Govind, N. and Wang, Y. A. and Carter, E. A.},
      Journal = {Phys. Rev. Lett.},
      Pages = {5954--5957},
      Volume = {86},
      Year = {2001},
      Month = jun, Number = {26},
      Abstract = {We present the first ab initio prediction of localized electronic excited states in a periodically infinite condensed phase, a heretofore intractable goal. In particular, we examined local excitations within a CO molecule adsorbed on Pd(111). The calculation allows a configuration interaction treatment of a local region, while its interaction with the extended condensed phase is described via an embedding potential obtained from periodic density functional theory. Our work lays the foundation of a microscopic understanding of photochemistry and spectroscopy on metal surfaces.},
      Url = {http://dx.doi.org/10.1103/PhysRevLett.86.5954} }
  • S. Thiel, M. Pykavy, T. Klüner, H. J. Freund, R. Kosloff, und V. Staemmler, "Three-dimensional ab initio quantum dynamics of the photodesorption of CO from Cr$_2$O$_3$(0001): Stereodynamic effects," Phys. Rev. Lett., vol. 87, iss. 7, p. 077601, 2001.
    @Article{Thiel2001, Title = {Three-dimensional ab initio quantum dynamics of the photodesorption of CO from Cr$_2$O$_3$(0001): Stereodynamic effects},
      Author = {Thiel, S. and Pykavy, M. and Klüner, T. and Freund, H. J. and Kosloff, R. and Staemmler, V.},
      Journal = {Phys. Rev. Lett.},
      Pages = {077601},
      Volume = {87},
      Year = {2001},
      Month = aug, Number = {7},
      Abstract = {Having performed the first three-dimensional ab initio quantum dynamical study of photodesorption from solid surfaces, we gained mechanistic understanding of the rotational alignment observed in die CO/Cr2O3(0001) system. Our study is based on potential energy surfaces obtained by embedded cluster calculations for both the electronic ground and excited state of the adsorbate substrate complex. Stochastic wave packet calculations demonstrate the importance of the angular degrees of freedom for the microscopic picture of the desorption process in addition to the desorption coordinate.},
      Url = {http://dx.doi.org/10.1103/PhysRevLett.87.077601} }
  • H. -J. Freund, T. Klüner, R. Wichtendahl, S. Thiel, M. Adelt, W. Drachsel, M. Bäumer, H. Kuhlenbeck, T. Risse, K. Al-Shamery, M. Kampling, und H. Hamann, "Molecules on clean and modified oxide surfaces.," NATO Science Series, Series C: Mathematical and Physical Sciences, vol. 546, iss. Metal-Ligand Interactions in Chemistry, Physics and Biology, pp. 91-128, 2000.
    @Article{Freund2000, Title = {Molecules on clean and modified oxide surfaces.},
      Author = {Freund, H.-J. and Klüner, T. and Wichtendahl, R. and Thiel, S. and Adelt, M. and Drachsel, W. and Bäumer, M. and Kuhlenbeck, H. and Risse, T. and Al-Shamery, K. and Kampling, M. and Hamann, H.},
      Journal = {NATO Science Series, Series C: Mathematical and Physical Sciences},
      Pages = {91--128},
      Volume = {546},
      Year = {2000},
      Number = {Metal-Ligand Interactions in Chemistry, Physics and Biology},
      Abstract = {A review with 150 refs. This paper reviews results obtained with a series of surface science methods on mols. adsorbed on well-ordered oxide surfaces. The exptl. data are compared with calcns. and it must be concluded that the understanding is far from satisfactory on a quant. scale, although qual. some progress has been made. This is particularly demonstrated for photostimulated desorption of NO from NiO. In a second part oxide supported metal aggregates are studied with respect to morphol., geometric, electronic and magnetic structures. Their interaction with adsorbed mols. is a further topic. Size dependent properties such as CO dissocn. probability and photostimulated methan dissocn. are discussed. [on SciFinder(R)]},
      Url = {http://dx.doi.org/10.1007/978-94-011-4245-8_5} }
  • T. Klüner, S. Thiel, und V. Staemmler, "Ab initio calculation of proton scattering from He(1s2s, $^1$S): a first-principles wavepacket study beyond the Born-Oppenheimer approximation," J. Phys. B, vol. 32, iss. 20, pp. 4931-4946, 1999.
    @Article{Kluener1999, Title = {Ab initio calculation of proton scattering from He(1s2s, $^1$S): a first-principles wavepacket study beyond the Born-Oppenheimer approximation},
      Author = {Klüner, T. and Thiel, S. and Staemmler, V.},
      Journal = {J. Phys. B},
      Pages = {4931--4946},
      Volume = {32},
      Year = {1999},
      Month = oct, Number = {20},
      Abstract = {A first-principles study of the scattering of protons from the lowest-metastable singlet state of He, He(1s2s, S-1) is reported. The ground state of HeH+ and the four lowest excited states of (1)Sigma symmetry are treated by means of full configuration-interaction (FCI) calculations in an extended basis set. From the adiabatic potential curves diabatic potentials and diabatic coupling elements are generated by means of a block-diagonalization scheme. Hartree-Fock orbitals, frozen orbitals and state-averaged natural orbitals are used for generating CI wavefunctions as well as for the quasi-diabatization. The diabatic potential curves and the off-diagonal coupling elements are used in wavepacket calculations to simulate the scattering of protons and deuterons from He-4(1s2s, S-1) and He-3(1s2s, S-1).},
      Url = {http://dx.doi.org/10.1088/0953-4075/32/20/310} }
  • T. Klüner, S. Thiel, H. -. J. Freund, und V. Staemmler, "Laser-induced desorption of NO from NiO(100): ab initio and wave packet calculations," Proceedings of the SPIE - The International Society for Optical Engineering, vol. 3272, p. I, 1998.
    @Article{Kluener1998c, Title = {Laser-induced desorption of NO from NiO(100): ab initio and wave packet calculations},
      Author = {Klüner, T. and Thiel, S. and Freund, H. -. J. and Staemmler, V.},
      Journal = {Proceedings of the SPIE - The International Society for Optical Engineering},
      Pages = {SPIE},
      Volume = {3272},
      Year = {1998},
      Abstract = {In this paper we discuss theoretical investigations of UV-laser-induced desorption of NO-molecules from nickel oxide-(100)-surfaces. We focus on the interpretation of experimental results (velocity-distributions of the desorbing molecules, rotational and vibrational distributions) by performing for the first time high quality ab initio configuration interaction calculations for the construction of two dimensional potential energy surfaces of the ground and excited states involved in the desorption process.},
      Url = {http://dx.doi.org/10.1117/12.307120} }
  • S. Thiel, T. Klüner, H. J. Freund, und R. Kosloff, "Velocity distributions after laser-induced desorption of NO from NiO(100) - The role of the angular coordinate," Isr. J. Chem., vol. 38, iss. 4, pp. 321-327, 1998.
    @Article{Thiel1998b, Title = {Velocity distributions after laser-induced desorption of NO from NiO(100) - The role of the angular coordinate},
      Author = {Thiel, S. and Klüner, T. and Freund, H. J. and Kosloff, R.},
      Journal = {Isr. J. Chem.},
      Pages = {321--327},
      Volume = {38},
      Year = {1998},
      Number = {4},
      Abstract = {The experimental velocity distributions of NO desorbing from a NiO(100)-surface are simulated using a time-dependent wave packet method. Including the polar angle between the surface normal and the adsorbate molecular axis yields bimodal distributions in the correct velocity range and reasonable desorption probabilities if a resonance lifetime on the order of 25 fs is assumed. For two-dimensional simulations, an angular-independent charge-transfer-state was chosen as excited state in order to investigate the influence of the electronic ground-state on the final state distributions. We compare our results with wave packet calculations using a representative ab initio angular-dependent excited-state potential energy surface using a three-dimensional Hamiltonian.},
      Url = {http://dx.doi.org/10.1002/ijch.199800037} }
  • T. Klüner, S. Thiel, H. J. Freund, und V. Staemmler, "The vibrational excitation of NO desorbing from NiO(100) after UV laser irradiation: Is NO^- a possible intermediate species?," Chem. Phys. Lett., vol. 294, iss. 4-5, pp. 413-418, 1998.
    @Article{Kluener1998, Title = {The vibrational excitation of NO desorbing from NiO(100) after UV laser irradiation: Is NO^{-} a possible intermediate species?},
      Author = {Klüner, T. and Thiel, S. and Freund, H. J. and Staemmler, V.},
      Journal = {Chem. Phys. Lett.},
      Pages = {413--418},
      Volume = {294},
      Year = {1998},
      Month = sep, Number = {4-5},
      Abstract = {We report on ab initio and wave packet calculations with the intention of simulating the vibrational excitation of NO desorbing from a NiO(100) surface after laser irradiation. The influence of the electrostatic field above the singly positively charged surface on the N-O equilibrium distance of the NO--like intermediate is investigated by Hartree-Fock calculations. It is shown that the field leads to a considerable shortening of the equilibrium bond length of NO-, whereas the equilibrium distance of the neutral NO molecule is only slightly modified. Taking this field effect into account, we are able to obtain quantitative agreement between experimental and theoretical vibrational state populations. (C) 1998 Elsevier Science B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/S0009-2614(98)00884-7} }
  • T. Klüner, H. J. Freund, V. Staemmler, und R. Kosloff, "Theoretical investigation of laser induced desorption of small molecules from oxide surfaces: A first principles study," Phys. Rev. Lett., vol. 80, iss. 23, pp. 5208-5211, 1998.
    @Article{Kluener1998a, Title = {Theoretical investigation of laser induced desorption of small molecules from oxide surfaces: A first principles study},
      Author = {Klüner, T. and Freund, H. J. and Staemmler, V. and Kosloff, R.},
      Journal = {Phys. Rev. Lett.},
      Pages = {5208--5211},
      Volume = {80},
      Year = {1998},
      Month = jun, Number = {23},
      Abstract = {State resolved laser induced desorption of NO molecules from a NiO(100) surface is studied theoretically. A full potential energy surface for the excited state was constructed by means of ab initio cluster calculations in addition to the potential energy surface for the ground state. Multidimensional wave packet calculations on these two surfaces allow a detailed simulation of experimental observables, such as velocity distributions and desorption probabilities, on a full ab initio basis.},
      Url = {http://dx.doi.org/10.1103/PhysRevLett.80.5208} }
  • S. Thiel, T. Klüner, M. Wilde, K. Al-Shamery, und H. J. Freund, "The role of the initial population of molecular vibrations in surface photochemistry," Chem. Phys., vol. 228, iss. 1-3, pp. 185-203, 1998.
    @Article{Thiel1998, Title = {The role of the initial population of molecular vibrations in surface photochemistry},
      Author = {Thiel, S. and Klüner, T. and Wilde, M. and Al-Shamery, K. and Freund, H. J.},
      Journal = {Chem. Phys.},
      Pages = {185--203},
      Volume = {228},
      Year = {1998},
      Month = mar, Number = {1-3},
      Abstract = {In a one-dimensional wavepacket study the role of thermal population of molecular vibrations within surface photochemistry is studied using a model potential adopted to the system NO/Cr2O3(0001). Simulations are made concerning the temperature dependence of the efficiency for W-laser induced desorption and of velocity distributions. The course of these observables as a function of temperature is strongly dependent on the lifetime of the excited state. The results are compared with experimental results on the temperature dependence of the non-thermal desorption of NO from the Cr2O3(0001) surface after excitation at 6.4 eV. The experimentally observed increase of desorption cross-sections by about a factor of 2 when changing the surface temperature between 100 and 300 K is simulated when assuming an average resonance lifetime on the order of 10 fs. The experimentally found increase of translational energy with increasing surface temperature by similar to 100 m/s is also consistent with theoretical results. (C) 1998 Elsevier Science B.V.},
      Url = {http://dx.doi.org/10.1016/S0301-0104(97)00326-1} }
  • S. Thiel, T. Klüner, und H. J. Freund, "Interference-effects in the laser-induced desorption of small molecules from surfaces: a model study," Chem. Phys., vol. 236, iss. 1-3, pp. 263-276, 1998.
    @Article{Thiel1998a, Title = {Interference-effects in the laser-induced desorption of small molecules from surfaces: a model study},
      Author = {Thiel, S. and Klüner, T. and Freund, H. J.},
      Journal = {Chem. Phys.},
      Pages = {263--276},
      Volume = {236},
      Year = {1998},
      Month = sep, Number = {1-3},
      Abstract = {A diabatic treatment of laser-induced desorption of small molecules from surfaces is considered to be an essential step of the theoretical quantum mechanical simulation of a DIET process on an ab initio basis. The consequences of this treatment are investigated especially with respect to the resulting velocity distributions of the desorbing species. The distributions of NO desorbing from nickel oxide surfaces are characterised by a bimodal structure. In our calculations the diabatic coupling between several investigated two-state systems is introduced via the off-diagonal elements of the Hamiltonian, which determines the time evolution of the quantum system. This procedure is the basis for a discussion of the experimentally observed features in the velocity distributions in terms of a coherent diabatic picture. (C) 1998 Elsevier Science B.V. All rights reserved.},
      Url = {http://dx.doi.org/10.1016/S0301-0104(98)00176-1} }
  • U. J. Katter, T. Risse, H. Schlienz, M. Beckendorf, T. Klüner, H. Hamann, und H. J. Freund, "ESR and TPD investigations of the adsorption of di-tert-butyl nitroxide on Au(111) and NiO(111). Evidence for long-range interactions," J. Magn. Reson., vol. 126, iss. 2, pp. 242-247, 1997.
    @Article{Katter1997, Title = {ESR and TPD investigations of the adsorption of di-tert-butyl nitroxide on Au(111) and NiO(111). Evidence for long-range interactions},
      Author = {Katter, U. J. and Risse, T. and Schlienz, H. and Beckendorf, M. and Klüner, T. and Hamann, H. and Freund, H. J.},
      Journal = {J. Magn. Reson.},
      Pages = {242--247},
      Volume = {126},
      Year = {1997},
      Month = jun, Number = {2},
      Abstract = {Electron spin resonance and temperature-programmed desorption spectra of thin layers of DTBN (di-tert-butyl nitroxide) adsorbed on Au(111) and NiO(111)/Au(111) surfaces have been measured. The temperature-programmed desorption data show a weak chemisorption of the DTBN molecules in the monolayer on both surfaces. On Au(111) as well as on NiO(111)/Au(111), the ESR signal from monolayer coverages is totally suppressed. This suppression continues into the multilayer regime on both substrates. Disturbances of the substrate/adsorbate interface have a strong influence on the range of the signal suppression. Possible reasons for this behavior are discussed. (C) 1997 Academic Press.},
      Url = {http://dx.doi.org/10.1006/jmre.1997.1155} }
  • U. J. Katter, T. Hill, T. Risse, H. Schlienz, M. Beckendorf, T. Klüner, H. Hamann, und H. J. Freund, "Adsorption of the stable radical Di-tert-butyl nitroxide (DTBN) on an epitaxially grown Al$_2$O$_3$ film," J. Phys. Chem. B, vol. 101, iss. 4, pp. 552-560, 1997.
    @Article{Katter1997a, Title = {Adsorption of the stable radical Di-tert-butyl nitroxide (DTBN) on an epitaxially grown Al$_2$O$_3$ film},
      Author = {Katter, U. J. and Hill, T. and Risse, T. and Schlienz, H. and Beckendorf, M. and Klüner, T. and Hamann, H. and Freund, H. J.},
      Journal = {J. Phys. Chem. B},
      Pages = {552--560},
      Volume = {101},
      Year = {1997},
      Month = jan, Number = {4},
      Abstract = {The system di-tert-butyl nitroxide (DTBN) adsorbed on a thin film of gamma-Al2O3(111) sown on a NiAl(110) single crystal has been studied with various surface science methods, including TPD, XPS, NEXAFS, and ESR line-shapes analysis. In the monolayer regime, two strong chemisorbed species with adsorption energies of 120 and 150 kJ/mol, respectively, are found after adsorption at 40 K. One species is ESR active and reveals distinct dynamic behavior above 200 K through cw ESR line-shape analysis. The second species is oriented with an angle of about 70 degrees between the surface normal and the N-O axis of the molecule, as the NEXAFS data show. Missing of the pi* resonance and the ESR inactivity suggest a direct participation of the half-filled pi* orbital located at the nitrogen atom in the bonding mechanism. Above 200 K, both adsorbed species exchange with each other. This could be followed by monitoring the temperature-dependent ESR intensity. Adsorption at room temperature leads to the formation of a third unstable species which is ESR active but shows a different ESR spectrum in comparison with the other ESR-active species. The accessibility of the nitrogen atom for bonding is discussed on the basis of high-quality ab initio calculations.},
      Url = {http://dx.doi.org/10.1021/jp961485+} }
  • U. J. Katter, T. Hill, T. Risse, H. Schlienz, M. Beckendorf, T. Klüner, H. Hamann, und H. J. Freund, "Dynamics of the stable radical di-tert-butyl nitroxide on an epitaxially grown Al$_2$O$_3$ film," J. Phys. Chem. B, vol. 101, iss. 19, pp. 3776-3780, 1997.
    @Article{Katter1997b, Title = {Dynamics of the stable radical di-tert-butyl nitroxide on an epitaxially grown Al$_2$O$_3$ film},
      Author = {Katter, U. J. and Hill, T. and Risse, T. and Schlienz, H. and Beckendorf, M. and Klüner, T. and Hamann, H. and Freund, H. J.},
      Journal = {J. Phys. Chem. B},
      Pages = {3776--3780},
      Volume = {101},
      Year = {1997},
      Month = may, Number = {19},
      Abstract = {The molecular dynamics of one monolayer adsorption species of di-tert-butyl nitroxide (DTBN) adsorbed on a thin film of gamma-Al2O3(111) grown on a NiAl(110) single crystal has been studied via ESR line-shape analysis. Below 200 K a rigid limit spectrum is found, above this temperature the changes in line shape are consistent with slow motions of the molecule. Best agreement between the experimental spectra and simulations is obtained using a ''moderate jump'' model with both Brownian diffusion and jump type contributions to the molecular dynamics. The motional processes have an activation energy of about 9 kJ/mol.},
      Url = {http://dx.doi.org/10.1021/jp963104y} }
  • T. Klüner, H. J. Freund, J. Freitag, und V. Staemmler, "Laser induced desorption of NO from NiO(100): Characterization of potential energy surfaces of excited states," J. Mol. Cat. A, vol. 119, iss. 1-3, p. 155, 1997.
    @Article{Kluener1997, Title = {Laser induced desorption of NO from NiO(100): Characterization of potential energy surfaces of excited states},
      Author = {Klüner, T. and Freund, H. J. and Freitag, J. and Staemmler, V.},
      Journal = {J. Mol. Cat. A},
      Pages = {155},
      Volume = {119},
      Year = {1997},
      Month = may, Number = {1-3},
      Abstract = {In order to interpret experimental results such as velocity flux distributions and rotational/vibrational populations of the state resolved UV-laser induced desorption of NO from NiO(100) ab initio calculations at the configuration interaction (CI) and complete active space self consistent field (CASSCF) levels have been performed for the electronic ground state and those excited states which are important for the desorption process. The NO/NiO(100) system was described by a NiO58--cluster embedded in a Madelung field of point charges with NO adsorbed in the on-top position on the central Ni2+ ion. Two-dimensional potential energy surfaces for several electronic states have been calculated as a function of the N-Ni distance and the tilt angle of NO towards the surface normal. The excited states involved in the desorption process are charge transfer states in which one electron is transferred from the oxygen 2p-shell into the NO 2 pi-orbitals. The dependence of the potential energy surfaces on the N-Ni distance is dominated by a strong Coulomb attraction between the NO- ion formed as an intermediate and the hole created within the cluster. The angular dependence of the potentials favours an upright adsorption geometry if NO- is approaching the surface. This offers an explanation of the strong coupling between translation and rotation, which has been observed experimentally for the system NO/NiO(100), as well as the absence of such a coupling in the system NO/NiO(111).},
      Url = {http://dx.doi.org/10.1016/S1381-1169(96)00479-7} }
  • T. Klüner, H. ‐J. Freund, J. Freitag, und V. Staemmler, "Laser‐induced desorption of NO from NiO(100): Abinitio calculations of potential surfaces for intermediate excited states," J. Chem. Phys., vol. 104, iss. 24, pp. 10030-10040, 1996.
    @Article{Kluener1996, Title = {Laser‐induced desorption of NO from NiO(100): Abinitio calculations of potential surfaces for intermediate excited states},
      Author = {Klüner, T. and Freund, H.‐J. and Freitag, J. and Staemmler, V.},
      Journal = {J. Chem. Phys.},
      Pages = {10030-10040},
      Volume = {104},
      Year = {1996},
      Number = {24},
      Url = {http://dx.doi.org/http://dx.doi.org/10.1063/1.471747} }
  • K. Al-Shamery, M. Menges, I. Beauport, B. Baumeister, T. Klüner, T. Mull, H. J. Freund, C. Fischer, P. Andresen, und al., "State and spatially resolved studies of UV-laser induced desorption of molecules from oxide surfaces," Proceedings of SPIE-The International Society for Optical Engineering, vol. 2125, iss. Laser Techniques for Surface Science, pp. 182-191, 1994.
    @Article{Al-Shamery1994, Title = {State and spatially resolved studies of UV-laser induced desorption of molecules from oxide surfaces},
      Author = {Al-Shamery, K. and Menges, M. and Beauport, I. and Baumeister, B. and Klüner, T. and Mull, Th. and Freund, H. J. and Fischer, C. and Andresen, P. and et, al.},
      Journal = {Proceedings of SPIE-The International Society for Optical Engineering},
      Pages = {182--191},
      Volume = {2125},
      Year = {1994},
      Number = {Laser Techniques for Surface Science},
      Abstract = {Quantum state resolved velocity distributions of NO desorbing from single crystal metal and oxide surfaces after a non-thermal excitation process with UV-photons have been studied by several groups in the past. To achieve a "complete" expt., it is necessary to det. in addn. the spatial distribution of the desorbing particles. The authors report on results of the detn. of angular distributions of desorbing NO via a new exptl. setup. Two systems were studied in detail (i.e., NO on NiO (100) and NO on NiO (111)). A model proposed previously is used to explain the exptl. results (i.e., the observation of bimodal velocity flux distributions). The bimodal signal is consistent with the existence of 2 desorption channels which are predicted to exhibit different angular distributions. This prediction is verified with the new exptl. setup. The comparison of the 2 crystallog. planes of NiO allows the authors to address the problem of the influence of the magnetic properties of the substrate on the population of different spin states of desorbing NO mols. Finally, some results gained with a CO detection system based on a (1+1') REMPI process using VUV photons are presented for the system CO/Cr2O3 (111). With this setup, the resoln. of rotational states in the desorbing particles is easy to achieve in contrast to the widely used (2+1) REMPI process of the same transition. [on SciFinder(R)]},
      Url = {http://dx.doi.org/10.1117/12.180846} }