Molecular Dynamics Simulations of Nonequilibrium Effects Associated with Thermally Activated Exothermic Reactions

Jerzy Gorecki¹ and Joanna Natalia Gorecka²

¹Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, PL-01-224 Warsaw, Poland
²Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, PL-02-668 Warsaw, Poland
E-mail: ¹grecki@ichf.edu.pl, ²gorec@ifpan.edu.pl

(Received May 16, 2000; Accepted June 16, 2000)

Keywords: Reaction, Nonequilibrium Effects, Molecular Dynamics

Abstract. In this paper we discuss the influence of nonequilibrium effects on the rate of a thermally activated, exothermic reaction. The system with a binary process A +A B + B +{energy} is considered as an example, on which we compare molecular dynamics simulations with a simple phenomenology based on the assumption that a nonequilibrium state can be characterized by many time dependent temperatures. A good agreement between results of both methods is observed. We have found that the rate constants are changed significantly by the nonequilibrium effects, which affects system's evolution.