A Quantum Cluster Equilibrium Theory for Multi-Component Liquids

Abstract

In this work, we present a new theory to treat multi-component liquids based on quantum-chemically calculated clusters. The starting point is the binary quantum cluster equilibrium theory that is able to treat binary systems. The theory provides one equation with two unknowns. In order to obtain another linearly independent equation, conservation of mass is used. However, increasing the amount of components leads to more unknowns and this requires linearly independent equations. We address this challenge by introducing a generalization of the conservation of arbitrary quantities, accompanied by a comprehensive mathematical proof. Furthermore, a case study for the application of the new theory to ternary mixtures of chloroform, methanol and water is presented. Calculated enthalpies of vaporization for the whole composition range are given, and populations or weights of the different clusters are visualized.