Molecular dynamics simulations of nonequilibrium spatial correlations in a reaction diffusion system

The mesoscopic description of a system with chemical reactions predicts that if the detailed balance condition is not satisfied, then nonequilibrium spatial correlations between concentrations of reactants may appear. The present work is concerned with molecular dynamics simulations of such correlations in a model system of “reacting” hard spheres. The simulations have shown that if the detailed balance condition is satisfied, then the nonequilibrium spatial correlations are absent. In a steady state for which the detailed balance condition is not satisfied, the nonequilibrium correlations are present and their spatial exponential decay predicted by the theory based on a master equation, is confirmed in our simulations.