Research & Publ. - Fachbereich Chemie an der RPTU

Research & Publications

of Prof. Dr. C. van Wüllen

Research

Our research area is Quantum Chemistry, that is, the application of quantum mechanics to chemical problems. More specifically, we want to calculate and understand the electronic structure of atoms and molecules, determine molecular structures and (spectroscopic) properties, and explore reaction pathways. Currently, we are focusing on the following subjects:

Development of Relativistic electronic structure methods

Current projects involve the development of two-component relativistic approaches. These approaches account for spin-orbit coupling self-consistently (i.e., from the very beginning of a calculation). Such methods are necessary to describe compounds of the transactinides ("superheavy elements").

Currently, methods to describe electronic excitations and to calculate n.m.r. chemical shifts are under development. These properties are strongly incluenced by spin-orbit coupling also for systems with only moderately heavy elements.

Transition-metal catalyzed organic reactions

In cooperation with the experimental group of J. Christoffers (now in Oldenburg), we are investigating Fe(III) and Cu(II) catalyzed additions of dicarbonyl compounds to acceptor-activated olefins (Michael addition). The current question is how the enantioselectivity in the Cu(II) catalyzed variant becomes effective and which factors influence it.

Electronic structure of transition metal oxide aggregates

At the heart of this project is the electronic structure of vanadium oxide clusters with one ore more vanadium atoms. We are interested in determining the spin symmtery of the ground state of these open-shell compounds, ionization potentials and electron detachment energies of neutral and charged species, the simulation of photoelectron and vibrational spectra, and the reactivity of small vanadium oxide cations towards small alkanes.

Magnetic properties of transition metal complexes

In cooperation with experimental groups, we want to understand magnetic (exchange) coupling iespecially in those cases where the established rules of the thumb are not "good enough". The calculation of magnetic anisotropy (property related to zero-field splitting) is a challenge for large multinuclear complexes with antiferromagnetic coupling.

List of Publications

105. K. Krämer, M. Schmitz, H. Kelm, C. van Wüllen, H.-J. Krüger

Unexpected Reduction of a Coordinated Diazapyridinophane Ligand bound to Chromium(III) Ion Leading to Delocalization of the Unpaired Electron across two Isolated Pyridine Units

Chem. Eur. J. 29, e202301099 (2023)

10.1002/chem.202301099

104. J. Groß, C. van Wüllen

Computational Study on a Transfer Hydrogenation Catalysed by a Ru(II) bis-pyrazolyl pyridine complex

Isr. J. Chem. 63, e202300019 (2023)

10.1002/ijch.202300019

103. C. van Wüllen, E. M. V. Kessler

Is [ReCl₄(CN)₂]²⁻ a good Building Block for Single Molecule Magnets? A Theoretical Investigation.

ChemRxiv. Cambridge: Cambridge Open Engage; 2022. This content is a preprint and has not been peer-reviewed.

doi.org/10.26434/chemrxiv-2022-jwc57

102. M. Tombers, J. Meyer, J. Meyer, A. Lawicki, V. Zamudio-Bayer, K. Hirsch, J. T. Lau, B. von Issendorff, A. Terasaki, T. A. Schlathölter, R. A. Hoekstra, S. Schmidt, A. K. Powell, E. Kessler, M. H. Prosenc, C. van Wüllen, G. Niedner-Schatteburg

Mn₁₂-acetate complexes studied as single molecules

Chem. Eur. J., 28, e202102592 (2022)

doi.org/10.1002/chem.202102592

101. T. Bodenstein, K. Fink, A. Heimermann, C. van Wüllen

Development and application of a complete active space spin-orbit configuration interaction program designed for molecule magnets

ChemPhysChem 23, e202102592 (2022)

doi.org/10.1002/cphc.202100648

100. A. Heimermann, C. van Wüllen

Analyzing Anisotropic Exchange in a Pentanuclear Os₂Ni₃Complex

Chem. Eur. J. 27, 15148–15158 (2021)

doi.org/10.1002/chem.202101972

99. Sree Ganesh Balasubramani, Guo P. Chen, Sonia Coriani, Michael Diedenhofen, Marius S. Frank, Yannick J. Franzke Filipp Furche, Robin Grotjahn, Michael E. Harding Christof Hättig, Arnim Hellweg, Benjamin Helmich-Paris, Christof Holzer, Uwe Huniar, Martin Kaupp, Alireza Marefat Khah, Sarah Karbalaei Khani, Thomas Müller, Fabian Mack, Brian D. Nguyen, Shane M. Parker, Eva Perlt, Dmitrij Rappoport, Kevin Reiter, Saswata Roy, Matthias Rückert, Gunnar Schmitz, Marek Sierka, Enrico Tapavicza, David P. Tew, Christoph van Wüllen, Vamsee K. Voora, Florian Weigend, Artur Wodyński, Jason M. Yu

TURBOMOLE: Modular program suite for ab initio quantum-chemical and condensedmatter simulations

J. Chem. Phys. 152, 184107 (2020)

doi.org/10.1063/5.0004635

98. C. Mehlich, C. van Wüllen

Hyperfine tensors for a model system for the oxygen evolving complex of photosystem II: calculation of the anisotropy shift that occurs beyond the strong exchange limit

Phys. Chem. Chem. Phys. 21, 22902–22909 (2019)

doi.org/10.1039/c9cp03629f

97. C. van Wüllen, J. Lang, G. Niedner-Schatteburg

Reply to the "Comment on "Magnetostructural correlations in isolated trinuclear iron(iii) oxo acetate complexes"' by M. Antkowiak, G. Kamieniarz and W. Florek, Phys. Chem. Chem. Phys., 2018, 20, DOI: 10.1039/C8CP04691C

Phys. Chem. Chem. Phys. 21, 505–506 (2019)

https://doi.org/10.1039/c8cp05926h

96. A. Heimermann, C. van Wüllen

Magnetic Moments of Small Cobalt Clusters Revisited: The Contribution of 3d and 4s Electrons

Int. J. Mass. Spectrom. 438, 135-141 (2019)

https://doi.org/10.1016/j.ijms.2019.01.004

95. C. Mehlich, C. van Wüllen

Broken Symmetry Approach to Magnetic Properties of Oligonuclear Transition Metal Complexes. Application to Hyperfine Tensors of Mixed-Valent Manganese Compounds

J. Phys. Chem. C 123, 7717–7730 (2019)

http://dx.doi.org/10.1021/acs.jpcc.8b05806

94. F. W. Patureau, J. Groß, J. M. Ernsting, C. van Wüllen, J. N. H. Reek

P-N Bridged Dinuclear Rh-METAMORPhos Complexes: NMR and Computational Studies

Eur. J. Inorg. Chem. 2018, 3761–3769 (2018)

http://dx.doi.org/10.1002/ejic.201800397

93. J. Lang, J. M. Hewer, J. Meyer, J. Schuchmann, C. van Wüllen, Niedner-Schatteburg, G

Magnetostructural correlation in isolated trinuclear iron(iii) oxo acetate complexes

Phys. Chem. Chem. Phys. 20, 16673–16685 (2018)

http://dx.doi.org/ 10.1039/c7cp07549a

92. F. Rupp, K. Chevalier, M. Graf, M. Schmitz, H. Kelm, A. Grün, M. Zimmer, M. Gerhards, C. van Wüllen, H.-J. Krüger, R. Diller

Spectroscopic, Structural, and Kinetic Investigation of the Ultrafast Spin Crossover in an Unusual Cobalt(II) Semiquinonate Radical Complex

Chem. Eur. J. 23, 2119 (2017)

http://dx.doi.org/10.1002/chem.201604546

91. C. van Wüllen, K. Schwing, C. Riehn, M. Gerhards

Editorial of the PCCP themed issue on "Physical Chemistry for Life Sciences''

Phys. Chem. Chem. Phys. 19, 10714 (2017)

http://dx.doi.org/10.1039/c7cp90069d

90. B. Helmich-Paris, C. Hättig, C. van Wüllen

Spin-Free CC2 Implementation of Induced Transitions between Singlet Ground and Triplet Excited States

J. Chem. Theor. Comput. 12, 1892 (2016)

http://dx.doi.org/10.1021/acs.jctc.5b01197

Erratum: J. Chem. Theor. Comput. 13, 3426 (2017)

89. J. Meyer, M. Tombers, C. van Wüllen, G. Niedner-Schatteburg, S. Peredkov, W. Eberhardt, M. Neeb, S. Palutke, M. Martins, W. Wurth

The spin and orbital contributions to the total magnetic moments of free Fe, Co, and Ni clusters

J. Chem. Phys. 143, 104302 (2015)

http://dx.doi.org/10.1063/1.4929482

88. M. Kleinschmidt, C. van Wüllen, C. M. Marian

Intersystem-crossing and phosphorescence rates in fac-Ir-III(ppy)(3): A theoretical study involving multi-reference configuration interaction wavefunctions

J. Chem. Phys. 142, 094301 (2015)

http://dx.doi.org/10.1063/1.4913513

87. A. Fromm, C. van Wüllen, D. Hackenberger, L. Gooßen

Mechanism of Cu/Pd-Catalyzed Decarboxylative Cross-Couplings: A DFT Investigation

J. Am. Chem. Soc. 136, 10007 (2014)

http://dx.doi.org/10.1021/ja503295x

86. F. Rupp, K. Chevalier, M. M. N. Wolf, H.-J. Krüger, C. van Wüllen, Y. Nosenko, G. Niedner-Schatteburg, C. Riehn, R. Diller

Photoinduced Processes in Cobalt-Complexes: Condensed Phase and Gas Phase

EPJ Web Conf. 41, 05045 (2013)

http://dx.doi.org/10.1051/epjconf/20134105045

85. E. Kessler, S. Schmitt, C. van Wüllen

Broken symmetry approach to density functional calculation of zero field splittings including anisotropic exchange interactions

J. Chem. Phys. 139, 184110 (2013)

http://dx.doi.org/10.1063/1.4828727

84. P. Jost, C. van Wüllen

Why spin contamination is a major problem in the calculation of spin-spin coupling in triplet biradicals

Phys. Chem. Chem. Phys. 15, 16426–16427 (2013)

http://dx.doi.org/ 10.1039/C3CP52568F

83. K. Muller, Y. Sun, A. Heimermann, F. Menges, G. Niedner-Schatteburg, C. van Wüllen, W. R. Thiel

Structure–Reactivity Relationships in the Hydrogenation of Carbon Dioxide with Ruthenium Complexes Bearing Pyridinylazolato Ligands

Chem. Eur. J. 19, 7825–7834 (2013)

http://dx.doi.org/ 10.1002/chem.201204199

82. C. van Wüllen

Magnetic anisotropy through cooperativity in multinuclear transition metal complexes: theoretical investigation of an anisotropic exchange mechanism

Mol. Phys. 111, 2392–2397 (2013)

http://dx.doi.org/ 10.1080/00268976.2013.796069

81. P. Schwerdtfeger, C. van Wüllen, J. R. Cheeseman

Breakdown of the pseudopotential approximation for magnetizabilities and electric multipole moments. II. The importance of gauge invariance for large-core semi-local pseudopotentials.

J. Chem. Phys. 137, 014107 (2012)

http://dx.doi.org/ 10.1063/1.4731465

80. C. van Wüllen

On the use of effective core potentials in the calculation of magnetic properties, such as magnetizabilites and magnetic shieldings

J. Chem. Phys. 136, 114110 (2012)

http://dx.doi.org/10.1063/1.3694535

79. C. van Wüllen

Negative Energy States in Relativistic Quantum Chemistry

Theor. Chem. Acc. 131, 1082 (2012)

http://dx.doi.org/10.1007/s00214-011-1082-x

78. B. S. Fox-Beyer and C. van Wüllen

Theoretical Modeling of the Adsorption of Thallium and Element 113 atoms on Gold using Two-Component Density Functional Methods with effective core potentials

Chem. Phys. 395, 95–103 (2012)

http://dx.doi.org/10.1016/j.chemphys.2011.04.029

77. S. Schmitt, P. Jost, C. van Wüllen

Zero-field splittings from density functional calculations. Analysis and improvement of known methods

J. Chem. Phys. 134, 194113 (2011)

http://dx.doi.org/10.1063/1.3590362

76. A. Zaitsevskii, A. V. Titov, A. A. Rusakov, C. van Wüllen

Ab initio study of element 113 – gold interactions

Chem. Phys. Lett. 508, 329–331 (2011)

http://dx.doi.org/10.1016/j.cplett.2011.04.062

75. C. van Wüllen

Shared-Memory Parallelization of the TURBOMOLE programs AOFORCE, ESCF and EGRAD: How to quickly parallelize legacy code

J. Comput. Chem. 32, 1195–1201 (2011)

http://dx.doi.org/10.1002/jcc.21692

74. A. Zaitsevskii, C. van Wüllen, A. V. Titov

Adsorption of element 112 on the gold surface: many-body wavefunction versus density functional theory

J. Chem. Phys. 132, 081102 (2010)

http://dx.doi.org/10.1063/1.3336403

73. A. Zaitsevskii, C. van Wüllen, E. A. Rykova, A. V. Titov

Two-component relativistic density functional theory modeling of the adsorption of element 114 (eka-lead) on gold

Phys. Chem. Chem. Phys.12, 4152–4156 (2010)

http://dx.doi.org/10.1039/b923875a

72. C. van Wüllen

A Quasirelativistic Two-component Density Functional and Hartree-Fock Program

Z. Phys. Chem. 224, 413–426 (2010)

http://dx.doi.org/10.1524/zpch.2010.6114

71. A. V. Zaitsevskii, C. van Wüllen, A. V. Titov

Relativistic pseudopotential model for superheavy elements: applications to chemistry of eka-Hg and eka-Pb

Russ. Chem. Rev.78, 1173–1181 (2009)

http://dx.doi.org/10.1070/RC2009v078n12ABEH004075

Uspekhi Khimii78, 1263–1272 (2009) (Russian Version)

70. C. van Wüllen

Broken symmetry approach to density functional calculation of magnetic anisotropy or zero field splittings for multinuclear complexes with antiferromagnetic coupling

J. Phys. Chem. A113, 11535–11540 (2009)

http://dx.doi.org/10.1021/jp902823m

69. C. van Wüllen

Magnetic anisotropy from density functional calculations. Comparison of different approaches: Mn₁₂O₁₂ acetate as a test case

J. Chem. Phys. 130, 194109 (2009)

http://dx.doi.org/10.1063/1.3134430

68. S. Yao, Y. Xiong, C. van Wüllen, M. Driess

From a N-Heterocyclic Silacyclopropene to Donor-Supported Silacyclopropylium Cations

Organometallics 28, 1610–1612 (2009)

http://dx.doi.org/10.1021/om801178g

67. C. van Wüllen

On the eigenfunctions of the Douglas-Kroll operator

Chem. Phys. 356, 199–204 (2009)

http://dx.doi.org/10.1016/j.chemphys.2008.10.018

66. C. van Wüllen, W. Klopper and D. Mukherjee

Electron correlation, molecular properties and relativity – A tribute to Werner Kutzelnigg

Chem. Phys. 356, vii–ix (2009)

http://dx.doi.org/10.1016/j.chemphys.2009.01.011

65. S. Yao, C. van Wüllen, M. Driess

Striking Reactivity of a Ylide-like Germylene toward Terminal Alkynes: [2+4] Cycloaddition versus C-H Bond Activation

Chem. Commun. 2008, 5393–5395

http://dx.doi.org/10.1039/b811952j

64. F. Wang, J. Gauss, C. van Wüllen

Closed-shell coupled-cluster theory with spin-orbit coupling

J. Chem. Phys.129, 064113 (2008)

http://dx.doi.org/10.1063/1.2968136

63. W. Wang, S. Yao, C. van Wüllen, M. Driess

A Cyclopentadienide Analogue Containing Divalent Germanium and a Heavy Cyclobutadiene-Like Dianion with an Unusal Ge₄ core

J. Am. Chem. Soc.130, 9640–9641 (2008)

http://dx.doi.org/10.1021/ja802502b

62. M. K. Armbruster, F. Weigend, C. van Wüllen, W. Klopper
Self-consistent Treatment of Spin-Orbit Interactions with Efficient Hartree-Fock and Density Functional Methods
Phys. Chem. Chem. Phys.10, 1748–1756 (2008)

http://dx.doi.org/10.1039/b717719d

61. S. Yao, C. van Wüllen, X.-Y. Sun, M. Driess

Dichotome Reaktivität eines stabilen Silylens gegenüber terminalen Alkinen: C-H-Insertion oder autokatalytische Bildung von Silacycloprop-3-en

Angew. Chem. 120, 3294–3297 (2008)

http://dx.doi.org/10.1002/ange.200704939

Dichotomic Reactivity of a Stable Silylene Toward Terminal Alkynes: Facile CH Bond Insertion Versus Autocatalytic Formation of Silacycloprop-3-ene

Angew. Chem. Int. Ed.47, 3250–3253 (2008)

http://dx.doi.org/10.1002/anie.200704939

60. S. Seidel, K. Seppelt, C. van Wüllen, X. Y. Sun

Das blaue Xe₄⁺Kation. Experimenteller Nachweis und theoretische Identifizierung

Angew. Chem. 119, 6838-6841 (2007)

http://dx.doi.org/10.1002/ange.200701688

The Blue Xe₄⁺ Cation. Experimental Detection and Theoretical Characterization

Angew. Chem. Int. Ed. 46, 6717–6720 (2007)

http://dx.doi.org/10.1002/anie.200701688

59. S. Yao, M. Brym, C. van Wüllen, M. Driess

From a Stable Silylene to an Isolable Silaformamide-Borane Complex with Considerable Silicon-Oxygen Double Bond Character

Angew. Chem.119, 4237–4240 (2007)

http://dx.doi.org/10.1002/ange.200700398

Angew. Chem. Int. Ed. 46, 4159–4162 (2007)

http://dx.doi.org/10.1002/anie.200700398

58. M. Pykavy and C. van Wüllen

A systematic quantum chemical investigation of the C–H bond

activation in methane by gas phase vanadium oxide cation VO⁺

J. Comput. Chem. 28, 2252–2259 (2007)

http://dx.doi.org/10.1002/jcc.20584

57. C. van Wüllen and N. Langermann

Gradients for Two-Component Quasirelativistic Methods. Application to dihalogenides of element 116.

J. Chem. Phys. 126, 114106 (2007)

http://dx.doi.org/10.1063/1.2711197

56. M. Driess, S. Yao, M. Brym, C. van Wüllen

Low-Valent Silicon Cations With Two-Coordinate Silicon and Aromatic Character

Angew. Chem.118, 6882–6885 (2006)

http://dx.doi.org/10.1002/anie.200602327

Angew. Chem. Int. Ed.45, 6730–6733 (2006)

http://dx.doi.org/10.1002/anie.200602327

55. J. Borowka and C. van Wüllen

Computational studies on the enantioselective Copper(II) catalyzed Michael reaction

J. Organomet. Chem.691, 4474–4479 (2006)

http://dx.doi.org/10.1016/j.jorganchem.2006.01.067

54. M. Driess, S. Yao, M. Brym, C. van Wüllen, D. Lentz

A New Type of N-Heterocyclic Silylene with Ambivalent Reactivity

J. Am. Chem. Soc.128, 9628–9629 (2006)

http://dx.doi.org/10.1021/ja062928i

53. M. Driess, S. L. Yao, M. Brym, C. van Wüllen

Ein Heterofulven-analoges Germylen mit Betain-Reaktivität

Angew. Chem.118, 4455–4458 (2006)

http://dx.doi.org/10.1002/ange.200600237

A Heterofulvene-Like Germylene with a Beatin-Reactivity

Angew. Chem. Int. Ed. 45, 4349–4352 (2006)

http://dx.doi.org/10.1002/anie.200600237

52. P. Escarpa Gaede and C. van Wüllen

Ligand Bridged Heterodinuclear Transition Metal Complexes – Syntheses, Structures and Electrochemical Investigations

Z. Allg. Anorg. Chem. 632, 541–552 (2006)

http://dx.doi.org/10.1002/zaac.200500229

51. A. V. Mitin and C. van Wüllen

Two-component relativistic density functional calculations of the dimers of the halogens from bromine through element 117 using effective core potential and all-electron methods

J. Chem. Phys. 124, 064305 (2006)

http://dx.doi.org/10.1063/1.2165175

50. C. van Wüllen

Numerical Instabilities in the Computation of Pseudopotential Matrix Elements

J. Comput. Chem, 27, 135–141 (2006)

http://dx.doi.org/10.1002/jcc.20325

49. C. van Wüllen

Buchrezension: W. Demtröder: “Molecular Physics: Theoretical Principles and Experimental Methods”

Angew. Chem.118, 5863–5864 (2006)

https://doi.org/10.1002/ange.200585402

Book review: W. Demtröder: “Molecular Physics: Theoretical Principles and Experimental Methods”

Angew. Chem. Int. Ed.45, 5733–5734 (2006)

https://doi.org/10.1002/anie.200585402

48. C. van Wüllen and C. Michauk

Accurate and Efficient Treatment of Two-Electron Contributions in Quasirelativistic high-order Douglas-Kroll Density Functional Calculations

J. Chem. Phys.123, 204113 (2005)

http://dx.doi.org/10.1063/1.2133731

47. D. Schröder, C. van Wüllen, H. Schwarz, T. Klapötke

Stabilität von gasförmigem Thalliummonofluorid: TlF⁰, TlF⁺ und TlF²⁺

Angew. Chem.117, 4326–4330 (2005)

http://dx.doi.org/10.1002/ange.200461334

Stability of Gaseous Thallium Monofluoride as TlF⁰, TlF⁺, and TlF²⁺

Angew. Chem. Int. Ed.44, 4254–4257 (2005)

http://dx.doi.org/10.1002/anie.200461334

46. R. Berger, N. Langermann, C. van Wüllen

Zeroth order regular approximation approach to molecular parity violation

Phys. Rev. A71, 042105 (2005)

http://dx.doi.org/10.1103/PhysRevA.71.042105

45. R. Berger and C. van Wüllen

Density functional calculations of molecular parity violating effects within the zeroth order regular approximation

J. Chem. Phys. 122, 134316 (2005)

http://dx.doi.org/10.1063/1.1869467

44. C. van Wüllen

Sixth-order Douglas-Kroll: Two-component reference data for one-electron ions from 1s_1/2 to 4f_7/2

Chem. Phys.311, 105–112 (2005)

http://dx.doi.org/10.1016/j.chemphys.2004.10.010

43. M. Dolg and C. van Wüllen

Relativistic effects in heavy-element chemistry and physics - in memoriam Bernd A. Heß (1954–2004)

Chem. Phys. 311, 1–2 (2005)

http://dx.doi.org/10.1016/j.chemphys.2004.11.003

42. D. Ambrosek, C. A. Chatzidimitriou-Dreismann, P. Krause, J. Manz, H. Naumann, C. van Wüllen

Attosecond dynamics of nuclear wavepackets induced by neutron Compton scattering

Chem. Phys.302, 229-241 (2004)

http://dx.doi.org/10.1016/j.chemphys.2004.03.019

41. C. van Wüllen

Relation between different variants of the generalized Douglas-Kroll transformation through sixth order

J. Chem. Phys. 120, 7307-7313 (2004)

http://dx.doi.org/10.1063/1.1687676

40. M. Pykavy, C. van Wüllen, J. Sauer

Electronic ground states of the V₂O₄^+/0/- species from multireference correlation and density functional studies

J. Chem. Phys.120, 4207-4215 (2004)

http://dx.doi.org/10.1063/1.1643891

39. S. Pelzer, T. Kauf, C. van Wüllen, J. Christoffers

Catalysis of the Michael Reaction by Iron(III): Calculations, Mechanistic Insights and Experimental Consequences

J. Organometallic Chem.684, 308-314 (2003)

http://dx.doi.org/10.1016/S0022-328X(03)00765-4

38. M. Pykavy and C. van Wüllen

Multireference Correlation Calculations for the Ground States of VO^+/0/- Using Correlation Consistent Basis Sets

J. Phys. Chem. A107, 5566-5572 (2003)

http://dx.doi.org/10.1021/jp027264n

37. C. van Wüllen

Buchrezension: “Handbook of Molecular Physics and Quantum Chemistry”. Band 1-3. Herausgegeben von Stephen Wilson, Peter F. Bernath und Roy McWeeny.

Angew. Chem.115, 5843 (2003)

https://doi.org/10.1002/ange.200385046

Book review: “Handbook of Molecular Physics and Quantum Chemistry”. Vols. 1-3. Edited by Stephen Wilson, Peter F. Bernath, and Roy McWeeny.

Angew. Chem. Int. Ed.42, 5667 (2003)

https://doi.org/10.1002/anie.200385046

36. C. van Wüllen

Web-Site: Spielerei verdeckt Nützliches

Angew. Chem. 115, 2156 (2003)

https://doi.org/10.1002/ange.200390479

web site: A playground with hidden treasures

Angew. Chem. Int. Ed.42, 2110 (2003)

http://dx.doi.org/10.1002/anie.200390453

35. H. Ackermann, J. Aust, M. Driess, K. Merz, C. Monsé, C. van Wüllen

How to tame planar and main group metal-substituted onium ions of phosphorus and arsenic

Phosphorus Sulf. Silic. Relat. Elem.177, 1613-1616 (2002)

http://dx.doi.org/10.1080/10426500290092776

34. C. van Wüllen

Spin Densities in Two-Component Relativistic Density Functional Calculations: Non-Collinear vs. Collinear Approach

J. Comput. Chem.23, 779-785 (2002)

http://dx.doi.org/10.1002/jcc.10043

33. W. Liu, C. van Wüllen, F. Wang, L. Li

Spectroscopic constants of MH and M2 (M = Tl, E113, Bi, E115): direct comparisons of four- and two-component approaches in the framework of relativistic density functional theory

J. Chem. Phys. 116, 3626-3634 (2002)

http://dx.doi.org/10.1063/1.1446026

32. M. Drieß, H. Ackermann, J. Aust, K. Merz, C. van Wüllen

As[P(NMe₂)₃]₂ als simultane As^I und P^I Quelle: Synthese und Dichtefunktionalrechnungen planar-tetrakoordinierter Arsonium- und Phosphoniumionen

Angew. Chem.114, 467-470 (2002)

http://dx.doi.org/10.1002/1521-3757(20020201)114:33.0.CO;2-6

As[P(NMe₂)₃]₂ as Simultaneous As^I and P^I Source: Synthesis and Density Function Calculations of Planar Tetracoordinate Arsonium and Phosphonium Ions

Angew. Chem. Int. Ed.41, 450-453 (2002)

http://dx.doi.org/10.1002/1521-3773(20020201)41:33.0.CO;2-N

31. W. Liu, C. van Wüllen, Y. K. Han, Y. J. Choi, Y. S. Lee

Spectroscopic constants of Pb and Eka-lead compounds: Comparison of different approaches

Adv. in Quantum Chem.39, 325-355 (2001)

http://dx.doi.org/10.1016/S0065-3276(05)39019-8

30. C. van Wüllen

Trendbericht Theoretische Chemie: Quantenchemie mit hoher Genauigkeit

Nachr. Chem. 49, 337-340 (2001)

http://dx.doi.org/ 10.1002/nadc.20010490310

29. M. Driess, C. Monsé, K. Merz, C. van Wüllen

Perstannylierte Ammonium- und Phosphoniumionen: metallorganische Onium- und gleichzeitig basenstabilisierte Stannyliumionen

Angew. Chem.112, 3838-3840 (2000)

http://dx.doi.org/10.1002/1521-3757(20001016)112:203.0.CO;2-G

Perstannylated Ammonium and Phosphonium Ions: Organometallic Onium Ions That Are also Base-Stabilized Stannylium Ions

Angew. Chem. Int. Ed.39, 3684-3686 (2000)

http://dx.doi.org/10.1002/1521-3773(20001016)39:203.0.CO;2-U

28. W. Liu and C. van Wüllen

Comment on "Four-component relativistic density functional calculations of heavy diatomic molecules" [J. Chem. Phys. 112, 3499 (2000)]

J. Chem. Phys.113, 2506-2507 (2000)

http://dx.doi.org/10.1063/1.482070

27. C. van Wüllen

A Comparison of Density Functional Methods for the Calculation of Phosphorus-31 NMR Chemical Shifts

Phys. Chem. Chem. Phys.2, 2137-2144 (2000)

http://dx.doi.org/10.1039/B000461H

26. W. Liu, W. Kutzelnigg, C. van Wüllen

Relativistic MCSCF by means of direct perturbation theory. II. Implementation and applications

J. Chem. Phys.112, 3559-3571 (2000)

http://dx.doi.org/10.1063/1.480510

25. C. van Wüllen

Book review: A. J. Stone, “The Theory of Intermolecular Forces”

Z. Physik. Chem.214, 113 (2000)

24. M. Drieß, J. Aust, K. Merz, C. van Wüllen

van’t-Hoff-Le-Bel-Fremdling: Bildung eines Phosphoniumkations mit einem planar-tetrakoordinierten Phosphoratom

Angew. Chem. 111, 3967-3969 (1999)

http://dx.doi.org/10.1002/(SICI)1521-3757(19991216)111:243.0.CO;2-F

van’t Hoff - Le Bel Stranger: Formation of Phosphonium Cations With a Planar Tetracoordinate Phosphorous Atom

Angew. Chem. Int. Ed. 38, 3677-3680 (1999)

http://dx.doi.org/10.1002/(SICI)1521-3773(19991216)38:243.0.CO;2-6

23. W. Liu and C. van Wüllen

Spectroscopic Constants of Gold and Eka-Gold (Element 111) Diatomic Compounds. The Importance of Spin-Orbit Coupling.

J. Chem. Phys.110, 3730-3735 (1999)

http://dx.doi.org/10.1063/1.478237

Erratum: J. Chem. Phys.113, 891 (2000)

http://dx.doi.org/10.1063/1.481866

22. C. van Wüllen

Relativistic All-Electron Density Functional Calculations

J. Comput. Chem.20, 51-62 (1999)

http://dx.doi.org/10.1002/(SICI)1096-987X(19980115)19:13.0.CO;2-Y

21. D. A. Herebian, C. S. Schmidt, W. S. Sheldrick, C. van Wüllen

eta(5)-Pentamethylcyclopentadienyliridium(III) and -rhodium(III) Labeling of Amino Acids with Aromatic Side-Chains. The Importance of Relativistic Effects for the Stability of Cp*Ir-III Sandwich Complexes

Eur. J. Inorg. Chem.1998, 1991-1998

http://dx.doi.org/10.1002/(SICI)1099-0682(199812)1998:123.0.CO;2-3

20. R. Franke and C. van Wüllen

First-order relativistic corrections to the MP2 energy from standard gradient codes. Comparison with results from density functional theory.

J. Comput. Chem..19, 1596-1603 (1998)

http://dx.doi.org/10.1002/(SICI)1096-987X(19981115)19:143.0.CO;2-E

19. C. van Wüllen

Molecular density functional calculations in the regular relativistic approximation. Method, application to coinage metal diatomics, hydrides, fluorides and chlorides, and comparison with first-order relativistic calculations.

J. Chem. Phys.109, 392-399 (1998)

http://dx.doi.org/10.1063/1.476576

18. C. van Wüllen

Molecular Structure and Binding Energies of Monosubstituted Hexacarbonyls of Chromium, Molybdenum, and Tungsten: Relativistic density functional study.

J. Comput. Chem.18, 1985-1992 (1997)

http://dx.doi.org/10.1002/(SICI)1096-987X(199712)18:163.0.CO;2-I

17. M. Kaupp, C. van Wüllen, R. Franke, F. Schmitz, W. Kutzelnigg

The Structure of XeF6 and of Compounds Isoelectronic with It. A Challenge to Computational Chemistry and to the Qualitative Theory of the Chemical Bond.

J. Am. Chem. Soc.118, 11939-11950 (1996)

http://dx.doi.org/10.1021/ja9621556

16. C. van Wüllen

A relativistic Kohn-Sham density functional procedure by means of direct perturbation theory II. Application to the molecular structure and bond dissociation energies of transition metal carbonyls and related complexes

J. Chem. Phys.105, 5485-5493 (1996)

http://dx.doi.org/10.1063/1.472389

15. C. van Wüllen

On the use of common effective core potentials in density functional calculations.

I. Test calculations on transition metal carbonyls

Int. J. Quantum Chem.58, 147-152 (1996)

http://dx.doi.org/10.1002/(SICI)1097-461X(1996)58:23.0.CO;2-Y

14. C. van Wüllen and W. Kutzelnigg

Calculation of nuclear magnetic resonance shieldings and magnetic susceptibilities using Multiconfiguration Hartree-Fock wave functions and local gauge origins

J. Chem. Phys.104, 2330-2340 (1996)

http://dx.doi.org/10.1063/1.470928

13. C. van Wüllen

Response to: “Comment on: Density functional calculation of nuclear magnetic resonance chemical shifts [J. Chem. Phys. 1996, 104, 1163]”

J. Chem. Phys.104, 1165-1165 (1996)

http://dx.doi.org/10.1063/1.470775

12. M. Bühl and C. van Wüllen

Computational evidence for a new C₈₄ isomer

Chem. Phys. Lett. 247, 63-68 (1995)

http://dx.doi.org/10.1016/0009-2614(95)01193-6

11. C. van Wüllen

A hybrid method for the evaluation of the matrix elements of the Coulomb potential

Chem. Phys. Lett.245, 648-652 (1995)

http://dx.doi.org/10.1016/0009-2614(95)01062-E

10. C. van Wüllen

A relativistic Kohn-Sham procedure by means of direct perturbation theory

J. Chem. Phys.103, 3589-3599 (1995)

http://dx.doi.org/10.1063/1.470242

9. A. Freitag, C. van Wüllen, V. Staemmler

An ab initio Study of the Chemical Bond and the ¹²⁹Xe NMR Chemical Shift in M⁺-Xe Compounds, M = Li, Na, K, Cu, Ag

Chem. Phys.192, 267-280 (1995)

http://dx.doi.org/10.1016/0301-0104(94)00399-U

8. C. van Wüllen

Density functional calculation of nuclear magnetic resonance chemical shifts

J. Chem. Phys.102, 2806-2811 (1995)

http://dx.doi.org/10.1063/1.468657

7. U. Fleischer, C. van Wüllen, W. Kutzelnigg

IGLO calculations of NMR chemical shifts in some silicon an phosphorus containing polycycles

Phosphorus Sulf. Silic. Relat. Elem. 93, 365-366 (1994)

http://dx.doi.org/10.1080/10426509408021859

6. C. van Wüllen, U. Fleischer, W. Kutzelnigg

Comment on ‘Theoretical calculations of the nuclear magnetic shielding tensors for the ethylenic carbon atoms in cyclopropenes’

Mol. Phys.81, 1373-1382 (1994)

http://dx.doi.org/10.1080/00268979400100931

5. C. van Wüllen

An Implementation of a Kohn-Sham density functional program using a Gaussian-type basis set. Application to the equilibrium geometries of C₆₀ and C₇₀.

Chem. Phys. Lett.219, 8-14 (1994)

dx.doi.org/10.1016/0009-2614(94)00062-X

4. C. van Wüllen

Magnetic properties of the BH molecule

Theoret. Chimica Acta87, 89-95 (1993)

dx.doi.org/10.1007/BF01113531

3. C. van Wüllen and W. Kutzelnigg

The MC-IGLO method

Chem. Phys. Lett.205, 563-571 (1993)

dx.doi.org/10.1016/0009-2614(93)80013-F

2. U. Meier, C. van Wüllen, M. Schindler

Ab initio Calculation of Magnetic Properties by the “Direct” IGLO Method