학술논문

Anisotropic rigid rotor potential energy function for H2O–H2.
Document Type
Article
Source
Journal of Chemical Physics. 10/1/1994, Vol. 101 Issue 7, p5824. 7p.
Subject
*POTENTIAL energy surfaces
*ANISOTROPY
*ELECTRICAL harmonics
*MOLECULAR dynamics
Language
ISSN
0021-9606
Abstract
We have calculated the interaction for H2O–H2 at 722 points on a five-dimensional surface where both molecules are treated as rigid rotators and we have fitted the ab initio points to a 48-term angular expansion of products of spherical harmonics and rotation matrices. The resulting potential energy function shows strong angle dependence with a large contribution from electrostatic interactions. When averaged over H2 orientations, the resulting water-atom-like surface is found to have zero crossing and minimum at similar distances to the corresponding H2O–He surface but to be generally more repulsive at short range and more attractive at long range. The isotropic average of the potential has a zero-crossing radius σ=3.05 Å and a well depth ε=49.5 cm-1 at an intermolecular separation Rm=3.52 Å. [ABSTRACT FROM AUTHOR]