Quant. relation between the retention values, the parameters a and c in retention equation lnk' = a + cCb and the solvatochromatic parameters in reversed-phase liquid chromatog. (RP-HPLC) were studied. The capacity factors of polar and nonpolar solutes at different organic modified concentration can be predicted by the solvatochromatic parameters through the prediction of parameters a and c. From the quant. relations of parameters a and c between the acetonitrile/water and methanol/water mobile phases, the hydrogen bonding solvatochromatic parameters play a significant role in improvement of the quant. relation.t

Key words: STRUCTURE PARAMETER, WATER, METHANOL, SOLUTE, ACETONITRILE, RETENTION-VALUE