The refractive indices (n(e) n(o)) and density have been measured at various temperature in the nematic-isotropic phases of nematogenic Methoxy-4(1)-Pentyl-4(1)-tolane. The molecular polarizability, nematic orientational order parameter are evaluated by Neugebauer anisotropic local field model. The distribution function f() and hence the higher order parameter P4 at different temperatures in the nematic phases have been estimated.