The Structure of Liquid Benzene.

The interactions of aromatic groups have been identified as playing a crucial role in many systems of interest. Unfortunately, conventional atom-centered force fields provide only an approximate representation of these molecules owing to their failure to consider the quadrupole moment arising from the π electrons. In this paper the structure of liquid benzene, the prototypical aromatic system, is investigated using a novel approach to Monte Carlo simulation, parametrized against experimental thermodynamic data, which incorporates an explicit representation of the aromatic π electrons. In contrast to previous simulations of liquid benzene it is found that a perpendicular arrangement of benzene molecules is preferred to a parallel arrangement. This result is in good agreement with experimental data.