Swain–Lupton equation

A dual parameter approach to the @[email protected] of substituent effects, which involves a field constant (\(F\)) and a @[email protected] constant (\(R\)). The original treatment was modified later. The procedure has been considerably applied, but also much criticized.
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1170 [Terms] [Paper]