Kirkwood-Fröhlich model for pure polar fluids

In this paper, we guide the reader to obtain the Kirkwood-Fröhlich equation for pure polar fluids. Such equation relates the dielectric constant of the fluid, its refractive index, its density, its temperature, and the permanent dipole moment of its constituent molecules, and also involves a dimensionless factor g – known as Kirkwood correlation factor – whose value is an expression of the correlation between the orientantions of the molecules of the fluid, in the case of zero external electric field.

Keywords
Dielectric constant; dielectrics; Kirkwood-Fröhlich model