List of refractive indices

Many materials have a well-characterized refractive index, but these indices often depend strongly upon the frequency of light, causing optical dispersion. Standard refractive index measurements are taken at the "yellow doublet" sodium D line, with a wavelength (λ) of 589 nanometers.

Refraction at interface

There are also weaker dependencies on temperature, pressure/stress, etc., as well on precise material compositions (presence of dopants, etc.); for many materials and typical conditions, however, these variations are at the percent level or less. Thus, it's especially important to cite the source for an index measurement if precision is required.

In general, an index of refraction is a complex number with both a real and imaginary part, where the latter indicates the strength of absorption loss at a particular wavelength—thus, the imaginary part is sometimes called the extinction coefficient ${\displaystyle k}$. Such losses become particularly significant, for example, in metals at short (e.g. visible) wavelengths, and must be included in any description of the refractive index.

Refraction, critical angle and total internal reflection of light at the interface between two media.

List

Some representative refractive indices

Name of material	λ (nm)	Refractive index no. n	Reference
Vacuum		1 (by definition)
Air at STP		1.000273	[citation needed]
Gases at 0 °C and 1 atm
Air	589.29	1.000293	[1]
Carbon dioxide	589.29	1.00045	[2][3][4]
Helium	589.29	1.000036	[1]
Hydrogen	589.29	1.000132	[1]
Liquids at 20 °C
Arsenic trisulfide and sulfur in methylene iodide		1.9	[5]
Carbon disulfide	589.29	1.628	[1]
Benzene	589.29	1.501	[1]
Carbon tetrachloride	589.29	1.461	[1]
Silicone oil (nD25)	589.29	1.393–1.403	[6]
Kerosene		1.44
Ethanol (ethyl alcohol)	589.29	1.361	[1]
Acetone		1.36
Water	589.29	1.333	[1]
10% glucose solution in water	589.29	1.3477	[7]
20% glucose solution in water	589.29	1.3635	[7]
60% glucose solution in water	589.29	1.4394	[7]
Solids at room temperature
Silicon carbide (moissanite; 6H form)	589.29	2.65	[8]
Titanium dioxide (rutile phase)	589.29	2.614	[9][10]
Diamond	589.29	2.417	[1]
Strontium titanate	589.29	2.41	[11]
Tantalum pentoxide	589.29	2.15	[12]
Amber	589.29	1.55	[1]
Sodium chloride	589.29	1.544	[13]
Fused silica (a pure form of glass, also called fused quartz)	589.29	1.458	[1][14]
Other materials
Liquid helium		1.025
Perfluorohexane (Fluorinert FC-72)		1.251	[15]
Water ice		1.31
TFE/PDD (Teflon AF)		1.315	[16][17]
Cryolite		1.338
Cytop		1.34	[18]
Polytetrafluoroethylene (Teflon)		1.35–1.38	[19]
Sugar solution, 25%		1.3723	[20]
Cornea (human)		1.373/1.380/1.401	[21]
Lens (human)		1.386–1.406
Liver (human)	964	1.369	[22]
Intestinal mucosa (human)	964	1.329–1.338	[23]
Ethylene tetrafluoroethylene (ETFE)		1.403	[24]
Sylgard 184 (polydimethylsiloxane)		1.4118	[25]
Sugar solution, 50%		1.4200	[20]
Polylactic acid		1.46	[26]
Pyrex (a borosilicate glass)		1.470	[27]
Vegetable oil		1.47	[28]
Glycerol		1.4729
Sugar solution, 75%		1.4774	[20]
Poly(methyl methacrylate) (PMMA)		1.4893–1.4899
Halite (rock salt)		1.516
Plate glass (window glass)		1.52	[29]
Crown glass (pure)		1.50–1.54
PETg		1.57
Polyethylene terephthalate (PET)		1.5750
Polycarbonate	150	1.60	[30]
Crown glass (impure)		1.485–1.755
Flint glass (pure)		1.60–1.62
Bromine		1.661
Flint glass (impure)		1.523–1.925
Sapphire		1.762–1.778
Boron nitride		2–2.14	[31]
Cubic zirconia		2.15–2.18	[32]
Potassium niobate (KNbO3)		2.28
Zinc oxide	390	2.4
Cinnabar (mercury sulfide)		3.02	Birefringent: nω = 2.905 nε = 3.256[33]
Silicon	1200 - 8500	3.42–3.48	[34]
Gallium(III) phosphide		3.5
Gallium(III) arsenide		3.927
Germanium	3000 - 16000	4.05–4.1	[35]

See also

• Sellmeier equation
• Corrective lens#Ophthalmic material property tables
• Optical properties of water and ice