Refractive index values are usually determined at standard temperature. A higher temperature means the liquid becomes less dense and less viscous, causing light to travel faster in the medium. ... This results in a larger value for the refractive index due to a larger ratio.

Is refractive index inversely proportional to temperature?

The refractive index is inversely proportional to both the temperature and the wavelength.

Why is the refractive index temperature dependent?

In a physical or chemical view, in a homologous series of liquids and/or solutions, the refractive index can be depended on the power of interaction between molecules. The molecules move faster when temperature increases and in this condition, the power of interaction between molecules becomes less.