Refractive index

The dimensionless optical material property refractive index is the ratio of the wavelength of light in vacuum to the wavelength in the material.

ElementRefractive index
1HHydrogengaseous: 1
2HeHeliumgaseous: 1
6CCarbonDiamond: 2.417
7NNitrogengaseous: 1
8OOxygengaseous: 1
9FFluorine1
10NeNeon1
15PPhosphorus1.001
16SSulfur1.001
17ClChlorine1
18ArArgon1
30ZnZinc1.002
33AsArsenic1.001
34SeSelenium1
35BrBromine1.001
36KrKrypton1
52TeTellurium1
54XeXenon1
80HgMercury1