Short Communication

Prediction of gas chromatography retention of BTEX and other substituted benzenes based on quantum chemical parameters

A. Morsali¹*, S. A. Beyramabadi ², M. R. Bozorgmehr¹  M. Raanaee³,

B. Keyvani³ and G. R. Jafari¹

¹Department of Chemistry, Faculty of Science, Islamic Azad University-Mashhad branch, Mashhad, Iran.

²Department of Chemistry, Faculty of Science, Islamic Azad University-Neyshabur branch, Neyshabur, Iran.

³Department of Chemistry, Faculty of Science, Islamic Azad University-Saveh branch, Saveh, Iran.

*Corresponding author. E-mail: almorsali@yahoo.com.  Fax: 0098 51 843 8032.

Accepted 17 December, 2009

   Abstract

Quantitative structure-retention relationship (QSRR) models for gas chromatography retention times of BTEX (benzene, toluene, xylenes and ethylbenzene) and other substituted benzenes on DB-624, DB-wax and DB-1 have been developed. The B3LYP hybrid density functional level in the Gaussian 03 program were used to calculate molecular parameters such as dipole moments (), molecular volumes (V), molecular radius (r), the lowest unoccupied molecular orbital (LUMO),  the highest occupied molecular orbital (HOMO), Mülliken charges (Q) and Mülliken negative charges with hydrogens summed into heavy atoms in molecule (Q_H). Using multiple linear regression method, the correlation between retention time and structural parameters was obtained. Empirical functions with high correlation coefficient are appropriate for the prediction of retention times of BTEX and similar compounds.

Key words: Gas chromatography, retention time, quantitative structure-retention relationship, density functional theory.