Computer simulation studies of anisotropic systems. The density and temperature dependence of the second rank orientational order parameter for the nematic phase of a Gay-Berne liquid crystal

The relative importance of anisotropic repulsive and attractive forces in stabilising a nematic liquid crystal may be assessed from the thermodynamic parameter Gamma= -(partial derivative lnT/partial derivative lnV)([P2]), where [P-2] is the second rank orientational order parameter. A previous attempt to determine this quantity for the nematic phase of a Gay-Berne system has given a value about twice as large as that found experimentally. Here we report the determination of Gamma from an extensive simulation study for a Gay-Berne system with parameters more appropriate for mesogenic molecules than those selected originally. (C) 1997 Elsevier Science B.V.