Thermodynamic data for nonmesomorphic solutes at infinite dilution in the nematic and isotropic phases of hexylcyanobiphenyl

Infinite dilution solute activity coefficients _o ² , partial molar excess enthalpies and entropies , and partial molar enthalpies ( ) and entropies ( ) of solution, obtained using gas-liquid chromatography (GLC), are reported for thirty nonmesomorphic solutes in the nematic and isotropic phases of p-n-hexyl-p-cyanobiphenyl (6CB). The solutes studied include normal and branched alkanes, alkenes and hexadienes (with some cis and trans isomers), and benzene. The results corroborate earlier studies on other members of the p-n-alkyl-p-cyanobiphenyl homologous series of liquid crystals. The results demonstrate the effect that solute structure (size, shape, flexibility, polarizability and polarity) has on the solution process. Thermodynamic data for the cis and trans isomers of 2-pentene and 2-hexene are examined. A method for the simultaneous examination of the effects of both solute and solvent structures on the solution process is suggested.