Retention in Gas Chromatography

The value of K varies with temperature in the following manner (see the entry Thermodynamics of Retention in Gas Chromatography)... 

McGregor, T.R. (1979) Connectivity parameters as predictors of retention in gas chromatography. 

Rohrschneider s approach is able to predict retention index values for solute s with known solute constants (a, through e) [283,288]. These are determined from AI values for the solute on at least five phases of known phase constants and solving the series of linear equations. The retention index of the solute on any phase of known phase constants (X through S ) can then be calculated from Eq. (2.8). The theoretical defects of the method for assigning intermolecular interactions do not apply to the prediction of retention index values. A mean error of about 6 index units was indicated in some calculations. The retention or retention index values for thousands of compounds can be calculated from literature compilations of solute descriptors and the system constants summarized in Tables 2.6 and 2.8 using the solvation parameter model [103]. The field of structure-driven prediction of retention in gas chromatography is not well developed at present and new approaches will likely emerge in the future. 

A scale was developed of relative hydrogen-bond basicity for a wide variety of compounds by means of their retention in gas chromatography. Results indicate that the... 

K. Ciazynska-Halarewicz, M. Helbin, P. Korzenecki and T. Kowaiska, Mathematical models of solute retention in gas chromatography as sources of thermodynamic data. Part IV. Aliphatic alcohols as the test analytes,/ Chromatogr. Set, 2007, 45, 492-499. 

Chromatographers have used this solubility parameter to predict chromatographic retention in gas chromatography and in LC. Assuming that both phases, stationary and mobile, are bulk fluids (i.e., LC), the retention factor ki of a solute is related to solubility parameters according to... 

---