Refractive index and Lorentz-Lorenz function of xenon liquid and vapour

Refractive index measurements have been carried out on xenon liquid and vapour in coexistence from -59.0°c to 16.5°c, and also on fluid xenon at temperatures above the critical point (16.59°c). The results of over 500 measurements indicate that the Lorentz-Lorenz function ( n 2 -1)/( n 2 +2)ρ remains constant to within ±3% over the whole density range studied (0.001 to 0.02 mol cm -3 ) and that at the critical point n c = 1.3799±0.0008 and LL c = 10.5±0.1 cm 3 mol -1 (λ = 5893 Angstrom).