Croatica Chemica Acta, Vol. 57 No. 5, 1984.
Original scientific paper
Do the VSEPR Points-on-a-Sphere Repulsions Simulate Quantum Interactions?
Lawrence S. Bartell
; Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, U.S.A.
Abstract
The Valence-Shell-Electron-Pair-Repulsion theory, in its Points-
on-a-Sphere (POS) variant has been heretofore almost exclusively
applied to molecular structure. It is shown that the POS
model also implies the form of the potential energy surface for ·
bending deformations of molecules. The extent to which this elementary
mechanical model simulates quantum mechanical interactions
in binary compounds of main-group elements is investigated
using recent EHT molecular orbital calculations to supplement the
rather sparse accumulation of experimental and ab initio characterizations
of potential surfaces. It is found that the POS force field,
in the main, parallels quantum quadratic and anharmonic components
so closely that it promises to become a useful tool in spectroscopic
and diffraction research. A simple effective force law
between repelling points, namely -CJV;i (r)/or ex r-<•+1>, accounts
well for the known data<. For experiment and ab initio theory, the
parameter s expressing the hardness of repulsions is about 4, while
for EHT computations with frozen VOIP values, interactions
Keywords
Hrčak ID:
194065
URI
Publication date:
14.1.1985.
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