Quantum Chemistry Calculation on Mineral Surface Chemistry Character of Apatite

In this paper, the Gaussian98W software package and the STO-3G basis set have been adopted to study the electric charge, main atomic orbital populations of some frontier molecular orbits and covalent bond level of main atom of apatite surface on the basis of the Hartree-Fock-Roothaan (RHF) method arising from quantum chemistry ab-initio calculation. In apatite crystal structure, the composition characteristics of some frontier molecular orbits and Fermi levels are discussed by means of DV-X_α calculations. The results show that the highest occupied molecular orbits (HOMO) and the lowest unoccupied molecular orbits (LUMO) of the apatite cluster are primarily composed of Ca₃₈ and P₃₉, which results in the strongest covalent bone make of Ca₃₈ and P₃₉. Meanwhile, The structure achieves a good chemical stability. Then these results can be used to help us predict the adsorption ability and surface activity of apatite.