A relationship between adsorption heat and structure of adsorbate molecule in NaX zeolite molecular sieves

In this paper, the molecular graphics techniques and the ab initio molecular orbital STO-3G calculations were adopted to study the molecular sizes and electronic structures of 24 molecules as adsorbate in the NaX zeolite. Further more, the interaction energies of various molecules with Na+ were studied by ab initio calculations. The results show that there exists a significant correlation between the adsorption heat and molecular polarizability of the alkane (R = 0.998, F = 831. 155, S = 1.241, N= 6). Meanwhile significant multivariate correlation was found between the adsorption heat and interaction energies of various molecules with Na+, molecular Van der Waals volumes and lowest unoccupied orbital energies, in which Na+ takes an important role as the intermediate.