Phase transitions in two- and three-dimensional fluids with internal quantum states: Computer simulations and theory

Abstract

The properties of model fluids are investigated, whose particles have classical degrees of freedom in two and three dimensions and two internal quantum states. Attractive interactions are ‘‘turned on,’’ when the internal states are hybridized, corresponding to molecules acquiring a ‘‘dipole’’ moment. The phase diagram of this system in the temperature‐density plane as well as the static and imaginary time correlations at various densities are investigated by path integral Monte Carlo simulations. These are compared with mean field theory predictions.