PAIR-WISE INTERACTIONS BY GAS-CHROMATOGRAPHY .6. INTERACTION FREE ENTHALPIES OF SOLUTES WITH PRIMARY METHOXYALKANE, CYANOALKANE AND ALKANETHIOL GROUPS

Three polar-type liquids, P, having methoxy, cyano or thiol substituents in primary positions on a branched paraffin skeleton were used as stationary phases. The molecules of these stationary liquids have the same form and nearly the same size as that of the non-polar parent branched paraffin, C78H158 (C78). Gas chromatographic retention data of some 150 molecular probes were measured on pure P-type liquids and on P/C78 mixtures with a volume fraction phi(P) of 0.50. Based on these data interaction free enthalpies could be calculated between a probe and the polar substituent, both at infinite dilution in the alkane solvent.