ALTERNATIVE HAMILTONIAN FOR MOLECULAR-DYNAMICS SIMULATIONS IN THE GRAND-CANONICAL ENSEMBLE

An alternative to the Hamiltonian of Çaǧin and Pettitt for performing molecular dynamics simulations in the grand canonical ensemble is presented and used as the basis for a new algorithm. The algorithm is tested on the ideal gas and the truncated and shifted Lennard-Jones fluid. Simulations are used to calculate the vapor-liquid coexistence points for the Lennard-Jones system and are found to be in agreement with previous calculations using Gibbs ensemble calculations and with the Nicolas equation of state. Simulations are also performed on the Lennard-Jones solid. © 1995 American Institute of Physics.