This dataset contains the indices of refraction for common materials. The values were taken from the CRC Handbook of Chemistry and Physics, 93rd edition.
To learn more about what an index of refraction means, please see this page on indices of refraction.
The values for Air, Ar, CH4, CI2, CO2, H2, He, N2, N2O, NO, O2, and SO2 were taken at standard temperature and pressure, for a wavelength of .5893 `mu m`. Note: the dataset doesn't facilitate proper subscript notation, so please allow the clunkier CH4, Cl2, etc.
The values for water are taken for different temperatures, but they're all for a wavelength of 226.5 `nm`.
The refractive indices for Ice, Acetone, Ethyl alcohol, Sugar solution(30%), Fluorite, Fused quartz, Glycerine, Sugar solution(80%), Typical crown glass, Crown glasses lower/upper bounds, Spectacle crown (C-1), Sodium chloride, Polystyrene lower/upper bounds, Carbon disulfide, Flint glasses lower/upper bounds, Heavy flint glass, Extra dense flint (EDF-3), Methylene iodide, Sapphire, Rare earth flint lower/upper bounds, Lanthanum flint lower/upper bounds, Arsenic trisulfide glass, and diamond all came from Hyperphysics's page of refractive indices. The wavelength for any of these refractive indices were not provided, so keep that in mind.
The refractive indices for popular optics glasses were provided by a refractive index database (refractiveindex.info). The values were all for 587.6 `nm`. The kinds of glass are BK7, BAF10, BAK1, FK51A, LASF9, SF5, SF10, and SF11.