The measurement of the absorption of UV–VIS radiation by a solute in a highly viscous or solid matrix at low temperature.
Source: PAC, 1988, 60, 1449. (Nomenclature, symbols, units and their usage in spectrochemical analysis - VII. Molecular absorption spectroscopy, ultraviolet and visible (UV/VIS) (Recommendations 1988)) on page 1452 [Terms] [Paper]