The intermolecular potential and the lattice energy of benzene

The dispersion energy contribution to the intermolecular potential in a benzene crystal is calculated as a sum of bond-bond interactions and, combined with empirical estimates of the short-range repulsive potentials, gives a total energy close to the experimental latent heat of sublimation. The calculated lattice energy is minimized at values of the unit cell dimensions which are within 3% of the experimental data. Effective ‘atom -atom’ attractive coefficients, derived from the calculated dispersive interactions, are related to empirical coefficients used by other workers.