A molecular theory of the dielectric permittivity of a nematic liquid crystal

We present a theory of the dielectric permittivity in which the intermolecular dipole-dipole correlations are treated explicitly. The results for the static permittivity agree with those which have previously been obtained by continuum calculations. The frequency dependence of the permittivity is related to two relaxation times which contain the effects of only short range intermolecular correlations. Approximate relationships are derived between these times and independently measurable properties.