Update and expansion of a system constant database for open-tubular columns used in gas chromatography

The solvation parameter model is used to characterize the retention properties of fused-silica, open-tubular columns precoated with poly(siloxanes) containing methyl, phenyl, 3,3,3-trifluoropropyl, and 3-cyanopropyl substituents, poly(ethylene glycol), binary stationary phase mixtures, and ionic liquid stationary phases. System constants at 20 °C intervals over the temperature range 60 - 140 °C are presented for 61 columns, and for 15 of these the temperature range is extended to > 200 °C and close to the maximum allowed operating temperature for the column. The Wayne State University 2025 (WSU-2025) compound descriptor database is used exclusively as the sole source for compound descriptors to unify the system constants with a verified descriptor database. A generic composition designation is employed for the classification of poly(dimethylsiloxane) columns, poly(dimethyldiphenylsiloxane) columns containing 5 % diphenylsiloxane monomer, poly(methylphenylsiloxane) columns, silarylene-siloxane copolymer columns engineered to emulate poly(dimethyldiphenylsiloxanes) containing 5 % diphenylsiloxane monomer, and poly(ethylene glycol) columns for which the within group variation of the system constants for columns from different sources are small compared to changes associated with the variation of monomer composition. The selectivity space is evaluated using principal component factor analysis and hierarchical cluster analysis and differences in column selectivity for nominally similar columns using system constant correlation plots with system constants over the temperature range 80 - 140 °C as variables. The influence of temperature on selectivity is evaluated using system maps created by the simultaneous plot of the column system constants as a continuous function of temperature.