The formal equation which relates the deviation from the Clausiusndash;Mossotti equation for the dielectric constant to the dipoles induced in a nonpolar molecular fluid by the external fieldhyphen;induced dipoles and the permanent multipole moments is taken as a starting point. The molecular integrals appearing in this equation are explicitly written in terms of anglehyphen;averaged and anglehyphen;dependent pair correlation functions for the fluid. The intermolecular interactions for N2and CO2are modeled as the sums of diatomic potential functions plus quadrupolar energies. Simulated pair correlation functions are used in a calculation of the twohyphen; and threehyphen;molecule contributions to the deviation from Clausiusndash;Mossotti behavior for liquid N2. Pair correlation functions calculated in the limit of zero density were used to evaluate second dielectric virial coefficients for N2at 300 and 124thinsp;deg;K and for CO2at 323thinsp;deg;K. A comparison with experiment is moderately satisfactory, considering the uncertainties in the parameters of the calculation. It is concluded that the contributions due to orientational correlations and to quadrupolehyphen;induced terms play an important role in determining the deviations from Clausiusndash;Mossotti behavior for the systems considered.
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