Extended Hole Theory of Liquids. II. Approximate Calculation of the Partition Function

Abstract

Theoretical expressions from an earlier paper for the partition function and thermodynamic properties and a linear approximation for the dependence of the cell free volume on the number of nearest neighbors in a given local configuration are used in order to calculate thermodynamic properties and an equation of state for the hole theory of liquids. The region of validity of the linear free volume approximation is discussed. Among the properties calculated are the second virial coefficient for the dilute gas, the equation of state, excess entropy and internal energy of the liquid and compressed gas, and critical properties. The results are found to be in better agreement with experiment than other liquid theories. Possible extension and corrections to the theory are discussed.