Statistics of nearest-neighbour dipole and exchange interactions

Abstract

High-temperature partition functions for nearest-neighbour dipole and exchange interactions on the simple cubic lattice are calculated as far as the terms in (1/kT)⁸. The results for the dipole case are used in a qualitative discussion of some aspects of the theory of polar liquids and solutions. The principal conclusions are that slow convergence probably makes the power series approach unsatisfactory in the theory of highly polar liquids, and even more unsatisfactory in the theory of solutions containing highly polar components. A simple evaluation of the averages over orientations of dipoles required in this and similar work is given in Appendix I.