Solute-Solvent Interactions From Gas Chromatographic Activity Coefficients and the Solvation Parameter Model for Nitrogen-Containing Stationary Phases

• Published in: Journal of chromatographic science Vol. 41; no. 4; pp. 215 - 222
• Main Author: Santiuste, José M.
• Format: Journal Article
• Language: English
• Published: Niles, IL Oxford University Press 01.04.2003; Preston Publications
• Subjects: Analytical chemistry; Chemistry; Chromatographic methods and physical methods associated with chromatography; Exact sciences and technology; Gas chromatographic methods; Gibbs free energy; Chromatographic retention; Enthalpy; Prediction; Activity coefficient; Excess parameter; Entropy; Gas chromatography; Solvation; Property structure relationship; Gas liquid chromatography; Thermodynamic properties; Organic compounds; Stationary phase
• ISSN: 0021-9665; 1945-239X
• DOI: 10.1093/chromsci/41.4.215

Infinite dilution gas-liquid chromatographic activity coefficients (γ) and excess thermodynamic molar partial magnitudes [Gibbs energy (GE), enthalpy (HE), and entropy (SE)] for 37 solutes of varied polarity on four stationary phases with −NH groups are obtained from partition coefficients taken from literature. Relationships between GE and SE with the 37 solutes' structure in terms of the molecular connectivity index (1χv) are investigated. Correlations of solute-solvent interactions calculated in light of the solvation parameter model for selected solutes and stationary phases are tested. The effect of the solute's structure, expressed as the molecular connectivity index, on the nonpolar (cavity formation and dispersion interaction) [c+l. log L(16)] and the effect of the dipole moment and of the activity coefficient on the dipolarity-polarizability interaction (sπ2H) are studied. The correlation between the nonpolar interaction with the athermal activity coefficient on the nonpolymeric stationary phases is also attempted. In addition, the influence of the stationary phase polarity on the solute-stationary phase interactions for a series of solutes is studied.