The direct determination of the temperature dependence of the refractive index of liquids and solids

Abstract

A technique is described which allows a direct determination of the temperature dependence of the refractive index of transparent liquids and solids. It consists of an interferometric examination of a liquid or solid whose temperature changed in time linearly. For all the tested liquids except water, delta n/ delta t was found to be constant in the range 25-60 degrees C. The values delta n/ delta t determined for H2O, C6H12 and CCl4, and the value of delta 2n/ delta t2 obtained for water, are in good agreement with literature.