Theory of freezing

Abstract

It is argued that the liquid solid transition is best studied with the liquid as the starting point. The density functional theory of freezing, due to Youssouff and the author is introduced; very simple calculations leading to bcc and fcc phases are presented. Improvements in the density functional and in numerical approximations are discussed. A few applications of possible special interest here, namely melting laws, the glassy state, low melting point metals, and phonon spectra from liquid structure factor, are outlined. The relative stability of cubic phases is analyzed in some detail. Applications to mertensitic and other structural transitions, as well as to structures in systems with anisotropic building blocks, are mentioned. Two ideas, both emphasizing intermediate range spatial order in dense liquids, pervade this talk:- the importance of the form of structural correlation functions (e.g. S(q)) and the need for thinking in Fourier space rather than real space.