molar refraction, \(R\)

https://doi.org/10.1351/goldbook.M03979
Function of the refractive index, n, given by R = V m n 2- 1 n 2 + 2, where V m is the molar volume.
Source:
Green Book, 2nd ed., p. 33 (https://dev.goldbook.iupac.org/files/pdf/green_book_2ed.pdf)