absorptivity [obsolete]

https://doi.org/10.1351/goldbook.A00044
@A00035@ divided by the optical path length. For very low @A00513@ it approximates the @A00037@ [within the approximation \((1 - e^{-A}) \sim A\)]. The use of this term is not recommended.
Source:
PAC, 1996, 68, 2223. (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2227 [Terms] [Paper]