Hydrogen bonding. 38. Effect of solute structure and mobile phase composition on reversed‐phase high‐performance liquid chromatographic capacity factors

Abstract Reversed‐phase HPLC capacity factors, as log k ′, have been correlated through the LFER equation: where k ′ is the capacity factor for a series of solutes in a given stationary phase–mobile phase system, and the explanatory variables are the solute descriptors: R 2 an excess molar refraction, π the dipolarity/polarizability, Σα the overall hydrogen‐bond acidity, Σβ the overall hydrogen‐bond basicity and V x the McGowan volume. This equation was applied to various C 18 stationary phases with methanol–water, acetonitrile–water and tetrahydrofuran–water buffered mobile phases. The solute and mobile phase factors that influence log k ′ values are set out, and a comparison is made between log k ′ values and water–octanol partition coefficients.