Coomber's relationship can be used to describe how the internal pressure and dielectric constant of a non-polar liquid are related.
As , which defines the internal pressure of a liquid, it can be found that:
where is equal to the number of molecules is the ionization potential of the liquid is a temperature dependent relation based on numerical constants of the pair summation from inter-particle geometry is the polarizability is the volume of the liquid where for most non-polar liquids
References Meeten, G.H., "Theoretical Basis for Coomber's Relationship", Nature Vol. 223, August 23, 1969