Hansch–Fujita π-constant

https://doi.org/10.1351/goldbook.11453

A constant that describes the contribution of a substituent to the octan-1-ol-water log P of a compound.

Source:
PAC, 2016, 88, 239. 'Glossary of terms used in computational drug design, part II (IUPAC Recommendations 2015)' on page 247 (https://doi.org/10.1515/pac-2012-1204)