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New Low-Index Liquid Refractive Index Standard: SRM 1922



Jennifer R. Verkouteren, Stefan D. Leigh


A new standard for the calibration of refractometers has been developed. Standard Reference Material (SRM) 1922 is a mineral oil with a refractive index nD=1.46945 at 20 C, which is within the range of the Brix scale (% sucrose). The change in index with temperature (dn/dT) has been characterized for the range 15 C-35 C to allow for calibrations within that range of temperatures. The refractive indices were measured at 5 wavelengths in the visible spectrum by using the method of minimum deviation with a {plus or minus}2-3x10-5 refractive index unit uncertainty at 20 C. The values of nD and dnD/dT were determined by fits of a two-term Cauchy function to the values at the measured wavelengths with a {plus or minus}6x10-5 refractive index unit uncertainty in nD at 20 C.
Fresenius Journal of Analytical Chemistry
No. 3


brix, refractive index, refractometry, standard, standard reference material


Verkouteren, J. and Leigh, S. (2000), New Low-Index Liquid Refractive Index Standard: SRM 1922, Fresenius Journal of Analytical Chemistry (Accessed April 21, 2024)
Created June 1, 2000, Updated February 19, 2017