Based on the molecular graphic theory, the first order of connectivity index (¹χ) and odd-even index (OEI) of 64 alkanes were calculated. Quantitative structure-property relationship (QSPR) study was carried out between these two topological indices and the chromatographic retention index, and the obtained multiple linear regression model was: RI＝55.7631＋25.7317OEI＋111.4508¹χ (R²＝0.9960, RMS＝9.36, ARD＝1.02%). Cross validation and prediction results show that this QSPR model is of good stability and powerful prediction ability. Compared with the reported result, not only the number of descriptors employed in this paper is much fewer, but also the calculation is much easier.

Key words: connectivity index (¹χ), odd-even index (OEI), alkane, chromatographic retention index, quantitative structure-property relationship (QSPR)