Polar embedded (PE) and C₁₈ reversed-phase liquid chromatographic (RPLC) stationary phases are useful media for studying interfacial sorption and partitioning mechanisms. Chromatographic retention parameters (t_r , k^/) were experimentally determined for a varied series of organic solutes including several commonly analyzed drug molecules on two complementary RPLC phases, (1) a new ether and sulfonamide embedded C₁₆ phase, and (2) a conventional C₁₈ phase of same particle size and phase loading. Acetonitrile (a non-HBD solvent) was used as the mobile phase so as to better isolate hydrogen bonding interactions between solutes and the embedded group on the PE phase. Correlation analyses between k^/ and individual solute molecular descriptors (a and V_x) suggest that retention on the PE phase is affected by interphase chain organization (due to PE group-silanol interactions) such that both solute a and V_x are relevant and that shape selectivity plays a role. Our observations are consistent with current proposed retention mechanisms on other PE RPLC phases.