selectivity factor

in ion exchange chromatography
https://doi.org/10.1351/goldbook.S05568
See: selectivity coefficient (in ion exchange chromatography)
Source:
PAC, 1993, 65, 819. 'Nomenclature for chromatography (IUPAC Recommendations 1993)' on page 857 (https://doi.org/10.1351/pac199365040819)