We present a report of our analysis of wave vector dependence of the static dielectric function of a dipolar liquid obtained by a microscopic calculation. At low values of the wave vector (k), the longitudinal dielectric function egr;(k) increases withk, in contradiction to some assumptions reported in the literature. As the value ofkis increased, egr;(k) diverges at a critical valuekcwhich depends on the value of the long wavelength static dielectric constant (egr;0) of the liquid. The dielectric function is negative for values ofkgreater thankc. At large values ofk, the calculated egr;(k) fails to attain the limiting value of unity. We attribute this result to the failure of the point dipole assumption made in the evaluation of the polarization correlation function required by the theory. The behavior of egr;(k) for the dipolar liquid is compared with that of one component plasma for which reliable results can be obtained over the full range of wave vectors. For both systems, the stability conditions are fulfilled at all values ofk. A plausible explanation of this rather exotic behavior of egr;(k) is given.
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