Theory of Phase Transitions in Solid Methanes. I. Electrostatic Multipole–Multipole Interaction

Abstract

A systematic method of studying the electrostatic interaction between two multipoles is presented. It is based on the quantum theory of angular momentum. A system of two interacting multipoles which have tetrahedral symmetry is worked out in detail. New expressions for the octopole–octopole, octopole–hexadecapole, and hexadecapole–hexadecapole interaction potentials are found which will be applied to the study of the molecular dynamics in solid methanes in the articles to follow.