Non-periodic boundary conditions for molecular simulations of condensed matter

A formally exact effective boundary potential is defined that can be combined with hard-wall boundary conditions to allow computer simulations to be performed that mimic an infinite system. The effective potential accounts for the interactions that would be present across the boundary if the system were truly infinite. The exact many-body potential is approximated by one- and two-body potentials. The algorithm is implemented and tested for a Lennard–Jones fluid. The advantages of the present formulation over the widely used periodic boundary conditions are discussed.