Generalized structural theory of freezing

Abstract

The first-principles order-parameter theory of freezing, proposed in an earlier work, has been successful in yielding quantitative agreement with known freezing parameters for monatomic liquids forming solids with one atom per unit cell. A generalization of this theory is presented to include the effects of a basis set of many atoms per unit cell. The basic equations are modified by the "density structure factors" $f_i$ which arise from the density variations within the unit cell. Calculations are presented for the important case of monatomic liquids freezing into hexagonal close packed solids. It is concluded that all freezing transitions can be described by using structural correlations in the liquid instead of the pair potential and that the three-body correlations are important in deciding the type of solid formed after freezing.