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Fermi Holes (fermi + hole)
Selected AbstractsAnalytic Models of Domain-Averaged Fermi Holes: A New Tool for the Study of the Nature of Chemical BondsCHEMISTRY - A EUROPEAN JOURNAL, Issue 11 2008Robert Ponec Prof. Abstract Simple analytical models are introduced that significantly enhance the ability to understand and rationalise the nature of bonding interactions depicted by domain-averaged Fermi hole (DAFH) analysis. The examples presented show that besides shedding new light on the role of electron-sharing in ordinary two-centre two-electron (2c,2e) chemical bonds that are well represented by the classical Lewis model, the proposed approach also provides interesting new insights into the nature of bonding interactions that go beyond the traditional Lewis paradigm. This is, for example, the case of 3c,2e multicentre bonding, but a straightforward extension of the approach also reveals for direct metal,metal bonding the existence of a completely new type of bonding interaction that involves the mutual exchange of electrons between the lone pairs on adjacent metal atoms. [source] Electron pairing and chemical bonds: Pair localization in ELF domains from the analysis of domain averaged Fermi holesJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 1 2007Robert Ponec Abstract This article reports the application of a recently proposed formalism of domain averaged Fermi holes to the problem of the localization of electron pairs in electron localization function (ELF) domains and its possible implications for the electron pair model of chemical bond. The main focus was on the systems, such as H2O or N2, in which the "unphysical" population of ELF domains makes the parallel between these domains and chemical bond questionable. On the basis of the results of the Fermi-hole analysis, we propose that the above problems could be due to the fact that in some cases the boundaries of the ELF domains need not be determined precisely enough. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006 [source] domain averaged Fermi holes;JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 15 2003chemical bond; The recently proposed approach based on the analysis of domain-averaged Fermi holes was applied to the study of the nature of metalmetal bonding in transition metal complexes and clusters. The main emphasis was put on the scrutiny of the systems assumed to contain direct multiple metalmetal bonds. The studied systems involve: (1) systems of the type M2X6 (M = Mo, W, X = CH3) anticipated to contain metalmetal triple bonds; (2) the molecule of W2Cl8(4,) as the representative of the systems with quadruple metalmetal bonding; (3) diatomic molecules Mo2 and V2 considered as the potential candidates for higher than quadruple metalmetal bonding. Although the resulting picture of bonding has been usually shown to agree with the original expectations based on early simple MO models, some examples were also found in which the conclusions of the reported analysis display dramatic sensitivity to the quality of the wave function used for the generation of the Fermi holes. In addition to this we also report some examples where the original theoretical predictions of multiplicity of metalmetal bonds have to be corrected. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 1829,1838, 2003 [source] | ||||||||||