On the Treatment of Electrostatic Interactions of Non-spherical Molecules in Equation of State Models

For predictive applications, equation of state (EOS) models have to describe all relevant physical interactions accurately. In this contribution, the vapor–liquid equilibria of various dipolar two-center Lennard-Jones model molecules are determined by molecular simulation, as function of molecular elongation and deflection angle of the dipole. It is shown that present PC-SAFT-based EOS models require additional adjustable parameters in order to describe the orientational effects of the dipole-moment. We present extensions of the model to avoid the additional parameters and apply the extended equations to model systems and real molecules.