On the relationship between two-body and three-body interactions from nonequilibrium molecular dynamics simulation

Nonequilibrium molecular dynamics (NEMD) simulations are performed for argo n at different strain rates using accurate two-body and three-body intermol ecular potentials. The contributions of two- and three-body interactions to the configurational energy of argon at different strain rates are reported . The NEMD data indicate that there is the same simple relationship between two- and three-body interactions as reported previously [Marcelli and Sadu s, J. Chem. Phys. 112, 6382 (2000)] from equilibrium Monte Carlo simulation s. The relationship is largely independent of strain rate. NEMD calculation s using this relationship for shear viscosity at different strain rates ind icate good agreement with full two-body+three-body calculations. This means that the effect of three-body interactions on transport properties might b e achieved in a conventional two-body NEMD simulation without incurring the computational penalty of three-body calculations. (C) 2001 American Instit ute of Physics.