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Electron Deformation Density Distributions in Binuclear Complexes of Transition Metals : Computation and Interpretation from AB Initio Molecular Orbital Wavefunctions

  • Marc Bénard

Abstract

The theoretical electron deformation density distributions obtained from ab initio MO wavefunctions for [C5H5Fe(CO)2]2, (n5-C5H5Ni)2C2H2, Cr2(O2CH)4 and Mo2(O2CH)4 are reviewed. Several sections of these distributions are displayed, together with their experimental counterpart. A systematic comparison is performed between the deformation density distributions and the results of the Mulliken population analysis obtained from the wavefunctions. This comparison provides a first rationalization of the electron deformation density pattern in the vicinity of a metal-metal axis. The strong dependence of this pattern upon the location of the metal in the periodic table, the specific character of d-orbitals relatively to the orbital expansion associated with covalent bonding, the influence of the depopulation of the external s orbital associated with transition metal complexation, are emphasized. It is shown that these factors, combined in some cases with the lack of a direct metal-metal bond, can account for the puzzling absence of charge accumulation detected in most deformation density distributions obtained for binuclear complexes.

Keywords

High Occupied Molecular Orbital Binuclear Complex Accumulation Region Mulliken Population Analysis Deformation Density 
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Copyright information

© Plenum Press, New York 1982

Authors and Affiliations

  • Marc Bénard
    • 1
  1. 1.E.R. n∘ 139 du C.N.R.S. Laboratoire de Chimie QuantiqueUniversité L. PasteurStrasbourgFrance

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