Intermolecular Potential of the Methane Dimer and Trimer

Authors

M. M. Szczesniak
G. Chalansinski
S. M. Cybulski
Steve Scheiner, Utah State UniversityFollow

Document Type

Article

Journal/Book Title

Journal of Chemical Physics

Publication Date

1990

Volume

93

First Page

4243

Last Page

4253

Abstract

The Heitler–London (HL) exchange energy is responsible for the anisotropy of the pair potential in methane. The equilibrium dimer structure is that which minimizes steric repulsion between hydrogens belonging to opposite subsystems. Dispersion energy, which represents a dominating attractive contribution, displays an orientation dependence which is the mirror image of that for HL exchange. The three‐body correction to the pair potential is a superposition of HL and second‐order exchange nonadditivities combined with the Axilrod–Teller dispersion nonadditivity. A great deal of cancellation between these terms results in near additivity of methane interactions in the long and intermediate regions.

Comments

Originally published by American Institute of Physics in the Journal of Chemical Physics.

Publisher's PDF can be accessed through the remote link.

Recommended Citation

Intermolecular potential of the methane dimer and trimer M. M. Szczesniak, G. Chalasinski, S. M. Cybulski, and S. Scheiner, J. Chem. Phys. 93, 4243 (1990), DOI:10.1063/1.458757