Efficient determination of Hugoniot states using classical molecular simulation techniques

Abstract

We present a methodology for the efficient calculation of the shock Hugoniot using standard molecular simulation techniques. The method is an extension of an equation of state methodology proposed by Erpenbeck [1992, Phys. Rev. A, 46, 6406] and is considered as an alternative to other methods that generate Hugoniot properties. We illustrate the methodology for shocked liquid N₂ using two different simulation methods: (a) the reactive Monte Carlo method for a reactive system; and (b) the molecular dynamics method for a non-reactive system. The method is shown to be accurate, stable and generally independent of the algorithm parameters. We find excellent agreement with results calculated by other previous simulation studies. The results show that the methodology provides a simulation tool capable of determining points on the shock Hugoniot from a single simulation in an efficient, straightforward manner. Further applications and extensions of the method are briefly discussed.