Analysis of the equations which describe the gas-chromatographic behavior of homologous series of organic compounds

Abstract

1. We have assessed the correlational and extrapolation possibilities of six equations, used in the literature to describe the dependence of corrected retainable volumes 1500 and retention indices on the serial number of the homolog (n), for the case of n-alkanes, secondary and tertiary aliphatic amines, sulfides, aldehydes, and methyl ketones. 2. The correlational possibility of equations which describe the change in retention indices is greater than that of equations which describe the corrected retention volumes. In homologous series, the dependence of GC-retention parameters on n cannot be described by another form of equation. The initial region is described by the nonlinear equation (4) and the subsequent region by a linear equation which can be used to determine the retention index for all homologs for which n ≥ 8 with reasonable accuracy. Both equations can be used for the GC identification of substances with the aid of a calculator.