Simulation of chemical reaction equilibria by the reaction ensemble Monte Carlo method: a review

Understanding and predicting the equilibrium behaviour of chemically reacting systems in highly non-ideal environments is critical to many fields of science and technology, including solvation, nanoporous materials, catalyst design, combustion and propulsion science, shock physics and many more. A method with recent success in predicting the equilibrium behaviour of reactions under non-ideal conditions is the reaction ensemble Monte Carlo method (RxMC). RxMC has been applied to reactions confined in porous solids or near solid surfaces, reactions at high temperature and/or high pressure, reactions in solution and at phase interfaces. The only required information is a description of the intermolecular forces among the system molecules and standard free-energy data for the reacting components. Extensions of the original method include its combination with algorithms for systems involving phase equilibria, constant-enthalpy and constant-internal energy adiabatic conditions, a method to include reaction kinetics, a method to study the dynamics of reacting systems, and a mesoscale method to simulate long-chain molecule phase separation. This manuscript surveys the various applications and adaptations of the RxMC method to date. Additionally, the relationship between the RxMC method and other techniques that simulate chemical reaction behaviour is given, along with insight into some technical nuances not found in the pioneering papers.