Molecular Theoretical Basis of Conventional Theories of Crystal-Melt Interface

A molecular theory of the crystal-melt interface is developed on the basis of statistical mechanical investigation of melting. From that point of view, the physical basis of existing conventional theories is explained, by paying a particular attention to Cahn's theory. On the way, the physical meaning of the Ising model appearing as a basic idea in those theories is clarified by comparing with the theory of ferromagnetism, and in consequence, the expressions for the relevant parameters in those theories are given in terms of the integrals concerning the pairwise potential between component atoms which are essential in understanding the melting. An important mathematical analogy between the present theory and the theory of ferromagnetism is effectively taken into consideration. At the same time, certain fundamental differences in physical interpretations existing between the both theories are emphasized.