Melting and the liquid and glassy states

Abstract

A unified model is presented which treats the melting, glass, and critical transitions by a single approach. It is shown that the important event in each case is the loss or gain of entropy associated with bifurcation of the on-site potential. This explains the first-order nature of the melting transition. Lindemann's melting rule is neither fundamental nor obeyed exactly. The relevance of various defects, invoked in earlier theories of the melting and glass transitions, lies in their providing favoured sites for bifurcation. Liquid helium II is believed to be unique in having bifurcated on-site potentials yet lacking the bifurcation entropy.