Aspects of an Unitary Classical Molecular Theory of the Crystalline and the Fluid State at Thermal Equilibrium

Abstract

AbstractIt is shown that, in spite of the existence of localized particles in crystals, an unitary partition function and grand partition function, resp., exists for the fluid and the crystalline state if an auxiliary external potential is introduced and, following BOGOLYUBOV'S idea, its zero limit is taken after carrying out the thermodynamic limit. Therefore, an unitary description of both the states (including the phase boundary between them) based on molecular distribution functions is possible. A new class of exact correlation functions characterizing localized particles is considered. The excess part of the free energy functional which results from a functional integration of the direct correlation function shows finite self‐interaction contributions of localized particles which must be removed by an additional renormalization procedure.