Quantitative relationships between the structure of alkylbenzenes and their gas chromatographic retention on stationary phases with different polarity

Vapour pressures and enthalpies of vaporization of a series of the linear n-alkyl-benzenes

“…As a rule, the isothermal Kovat's indices are only slightly dependent on the GC-oven temperature [42]. There are some comprehensive libraries containing retention values of alkyl-benzenes and other compounds available from the literature [38][39][40][41][42][43][44][45][46]. The Sadtler Standard…”

Comparison of methods for prediction of the retention data of aromatic hydrocarbons on UCON LB 550X and on polydimethylsiloxane

“…The exception is 1,7-dimethylnaphthalene, the experimental value of which was not included in the regression analysis for computation of the unified retention index, because it is much different from the other experimental retention data taken into account [20]. Comparison of measured retention indexes of selected alkylbenzenes on UCON LB 550X [3,14,19] with values predicted by use of Eqs. As Eqs (5)-(7) are based on Engewald's experimental data, which were also used for the comparison, the calculated differences are in the range expected, except for those from Eq.…”

“…This could, therefore, be an explanation of the difference obtained. (1)-(4),recommended in the literature [3,4],and by use of the unified retention index concept [2],Eq. (5).…”

“…The examination was directed towards methods based on detailed statistical analysis of the retention of alkylbenzenes [3][4][5] and alkylnaphthalenes [6][7][8] on UCON LB 550X and polydimethylsiloxane as a function of their physical properties (boiling point, molar volume, molar refraction) and topological properties (connectivity and complexity indexes), and tuning contributors [3], and on the unified retention index concept [2,9]. The best correlation equations [4,5] sum of the absolute charges of the carbon atoms in the functional group; qB takes into account the charges of carbon atoms at the ~ position to the aromatic ring; qTis the sum of the absolute charges of all carbon atoms in the solute molecule [11]; Lmax is the maximum geometric distance between the atoms of the solute molecule, and e is L'Haya's electropy index [12,13].…”

“…The best correlation equations [4,5] sum of the absolute charges of the carbon atoms in the functional group; qB takes into account the charges of carbon atoms at the ~ position to the aromatic ring; qTis the sum of the absolute charges of all carbon atoms in the solute molecule [11]; Lmax is the maximum geometric distance between the atoms of the solute molecule, and e is L'Haya's electropy index [12,13]. (3) is obtained from Dimov's experimental data [3] whereas in Eq. (3) is obtained from Dimov's experimental data [3] whereas in Eq.…”