Abstract: In this paper, the molecular graphics techniques and the ab initio molecular orbital STO-3Gcal-culations were adopted to study the molecular sizes and electronic structures of 24 molecules as adsorbate inthe NaX zeolite.Further more, the interaction energies of various molecules with Na⁺ were studied by abinitio calculations.The results show that there exists a significant correlation between the adsorption heatand molecular polarizability of the alkane(R= 0.998, F= 831.155, S=1.241, N= 6).Meanwhile signif-icant multivariate correlation was found between the adsorption heat and interaction energies of variousmolecules with Na⁺, molecular Van der Waals volumes and lowest unoccupied orbital energies, in which Na⁺ takes an important role as the intermediate.

Key words: NaX zeolite, Adsorbate, Ab initio, Molecular graphics techniques, Quantitative structure-property relationship