Gillespie-Nyholm

The Gillespie-Nyholm rules usually can also be applied to other polyanionic compounds with hypervalent atoms. As an example, some polytellurides are depicted in Fig. 13.6. The Te

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The Gillespie-Nyholm rules can be applied with the aid of this formulation. The occurrence of both kinds of building blocks in Li2Sb, chains and dumbbells, shows that in this case the Peierls distortion contributes only a minor stabilization and is partially overridden by other effects. The Peierls distortion cannot be suppressed that easily with lighter elements. 

The fundamental basis for the VSEPR model is provided by the Pauli principle and not by electrostatics. The fundamental assumption of the model is that the electron pairs in the valence shell of an atom keep as far apart as possible, in other words they appear to repel each other. Electrons exhibit this behavior as a consequence of the Pauli exclusion principle of same spin electrons and not primarily as a consequence of their electrostatic repulsion. The role of the Pauli principle was clearly stated in the first papers on the VSEPR model (Gillespie Nyholm, 1957 Gillespie Nyholm, 1958) but this role has sometimes been ignored and the model has been incorrectly presented in terms of electrostatics. 

It means, for example, that atomic data can only rarely be used as a substitute for molecular integrals since the atom-in-molecule orbitals are not the same as the separate atom orbitals — worse, they are no longer equivalent among themselves. An atomic self-repulsion integral (0j0, 0j0j) is different if 0j is the lone-pair hybrid of NH3 or the bond-pair hybrid as the Gillespie-Nyholm rules suggest. 

Gibson model, 38 174-176 Gillespie-Nyholm valence shell electron-pair repulsion theory, 18 325 Glass-formers , 4 294 Glauber s salt, 4 17... 

Transferability of ionic domains The Lewis S4)-Sidgwick-Powell 66)-Gillespie-Nyholm S6> rule... 

According to the VSEPR, Gillespie-Nyholm mles, the triatomic iso- and heteropolyhalogen cations, X3, X Ya, XaV" and YXZ are expected to be of bent strac-... 

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