A MOLECULAR STATISTICAL-THEORY OF NEMATIC LIQUID-CRYSTALS (THE EFFECTS OF A PAIR SPATIAL CORRELATION-FUNCTION)

The pair spatial correlation function is introduced approximately into mean field theory in terms of an orientation-averaged pair potential, and its effects on nematic-isotropic phase transition are investigated in detail. One finds that the anisotropy of the pairwise intermolecular potential and of the molecular shape account for the stability of nematic order, i. e. increase the long-range orientational order and also the transition temperature. The results of the numerical calculations are compared with experimental data for PAA and with other theoretical results.