Long-range contribution to inverse-distance power and Morse energy and pressure terms of a molecular liquid, tested on benzene

Analytical expressions were derived to estimate the contribution to the intermolecular energy and pressure from pairs of rigid molecules farther than a cutoff distance; inverse power terms (like in the Lennard-Jones potential) and exponential terms (like in the Morse potential) were considered. The Lennard-Jones case was tested on liquid benzene at room temperature in the Gibbs ensemble using the cavity-biased technique. The density produced by simulations using the derived cutoff correction was found to be independent of the cutoff used.