|WTT User's Guide
||Properties and Implemented Models
Index of Refraction The index of refraction nD is ratio between the speed of light in the
specified medium to the speed of light in a vacuum, represented as a function of
wavelength WL and temperature T. While the system state is
technically dependent on pressure p, experimental
data is not sufficiently constraining to justify including such a term.
The refractive index is dimensionless.
|nD = a + b×t + ∑ci×wi, i ∈ [1, nterms - 2]
|t = T - 298.15 K
|w = WL - 589.26 nm
where WL = wave length
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The TRC Group is part of the Thermophysical Properties Division in NIST's Material Measurement Laboratory
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