In this paper is presented an extension of the density dependence in the La
ndau-de Gennes theory for the nematic to isotropic phase transition, taking
into account this dependence for three phenomenological coefficients in th
e free energy expansion. In this manner, a better agreement between the cal
culated thermodynamic quantities and their experimental values was obtained
near the nematic-isotropic phase transition. More. the theory leads to a b
etter description of the temperature dependence of the order parameter in t
he same temperature range.