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Thermodynamic parameters of ΔH(T0), ΔS(T0), and ΔCP for 156 compounds comprising alkanes, alkyl halides and alcohols were determined for a 5% phenyl 95% methyl stationary phase. The determination of thermodynamic parameters relies on a Nelder-Mead simplex optimization to rapidly obtain the parameters. Two methodologies of external and leave one out cross validations were applied to assess the robustness of the estimations of thermodynamic parameters. The largest absolute errors in predicted retention time across all temperature ramps and all compounds were 1.5 and 0.3s for external and internal sets, respectively. The possibility of an in silico extension of the thermodynamic library was tested using a quantitative structure-retention relationship (QSRR) methodology. The estimated thermodynamic parameters were utilized to develop QSRR models. Individual partial least squares (PLS) models were developed for each of the three classes of the molecules. R² values for the test sets of all models across all temperature ramps were larger than 0.99 and the average of relative errors in retention time predictions of the test sets for alkanes, alcohols, and alkyl halides were 1.8%, 2.4%, and 2.5%, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new method for normalizing thermodynamic data between columns with varying dimensions. [•] Employs the use of simple standards and techniques available to any laboratory. [•] Provides accurate estimates for analyte retention between columns. [•] Average error in predicted retention across columns was 1.6s. [ABSTRACT FROM AUTHOR]

Highlights: [•] Thermodynamic parameters for 20 compounds determined in 2h. [•] Accurate retention time predictions using thermodynamic model. [•] Predictions in both GC and GC×GC modes. [ABSTRACT FROM AUTHOR]