Molecular Simulation of Shocked Materials Using Reaction Ensemble Monte Carlo: Part 1. Application to Nitrogen Dissociation

We demonstrate the applicability of the Reaction Ensemble Monte Carlo RxMC simulation method for calculating the shock Hugoniot properties of a material. The method does not require interaction potentials that simulate bond breaking or bond forming it requires only the intermolecular potentials and the ideal-gas partition functions for the reactive species that are present. By performing Monte Carlo sampling of forward and reverse reaction steps, RxMC provides information on the chemical equilibria states of the shocked material including the density of the reactive mixture and the mole fractions of the reactive species. We illustrate the methodology for shocked liquid N2, where we find excellent agreement with experimental measurements. This is the first of two reports describing the applicability of the RxMC method to simulating the shock Hugoniot properties of materials.