PATH-INTEGRAL GRAND-CANONICAL MONTE-CARLO

We derive the real-space path integral formulations of Widom's test pa rticle method and grand canonical Monte Carlo (GCMC). We apply these s imulation methods to hydrogen and neon at temperatures ranging from 30 to 120 K. In addition, in order to explore configuration space both e fficiently and ergodically, our implementation involves multiple time step hybrid Monte Carlo. Agreement between experiment and simulation f or chemical potentials (Widom) and densities (GCMC) is very good over the entire temperature range, even when quantum effects are large. (C) 1997 American Institute of Physics.