Application Of Mineral Surface Studying By Quantum Chemistry Method

With the development of science technology, study of the characteristics of mineral materials was intensively undertaken. On the basis of the quantum chemistry theories and methods the lots of different mineral's (apatite, diamond, turquoise, calcite, tourmaline) surface chemistry characteristics and structure energy of minerals were investigated in this thesis, At the same time, applications of these minerals, based on their surface characteristics have been discussed. According to the quantum chemistry calculations of the mineral it is clear that the results of theory calculation are consistent with the characteristics of mineral's structure.The charge, some frontier molecular orbitals and so on of the apatite surface been studied by ab-initio calculation. In crystal structure of apatite, the composition characteristic of some frontier molecular orbital and the Fermi levels have been discussed by DV-X_α calculations. The results show that the apatite cluster has higher chemical activiting. The results also prove that the adsorption capability and surface activity of apatite at the different crystal location has only little variance.In this study, the octahedron(111), cube(100) and dodecahedron(110) surfaces of diamond have been investigated by quantum chemistry calculations. The atom orbital populations and the energy of the diamond surfaces molecular orbital were obtained; the results show that cleavage and hardness of diamond were depended on the surface structure of diamond. The results also prove that the octahedron (111) surface of diamond is the steadiest than other crystal surfaces.The charge, some frontier molecular orbitals and so on of turquoise surface have been studied by quantum chemistry ab-initio method. Comparing Cu²⁺ turquoise with Fe³⁺ turquoise and Zn²⁺ turquoise, this research result indicates that H₂O at three kinds of turquoise crystal surface took place adsorption; the calculation results show that H₂O at the Fe³⁺ turquoise crystal surface is most stable than others.Environmental issue has caused widely public concern. In this thesis, the mechanism of calcite cluster structure absorbing environmental infectant has been investigated using quantum chemistry calculation. Using B3LYP calculation method and taking 6-311++G (3df,2pd) basis set in our Gaussian calculations, the results show that the calcite cluster structure can absorb environmental infectant. Thus these researches may offer theory basis of study of adsorption mechanism of calcite surface.Ab initio calculations of the surface structure and properties of the tourmaline cluster have been performed using different method. Relaxations are presented based on calculations employing the HF, B3LYP methals and taking STO-3G(3d,3p) , 6-31G(3d,3p) and 6-311++G(3df,3pd) basis set. Both Gaussian and density function and discrete variation method (DFT-DVM) have been used, in order to determine what extent computational factors are influences the result. The results show that using B3LYP and 6-31++1G(3df, 3pd) basis set methods calculation is expected to yield more accurate emerging values than other methods. Then using the quantum chemistry method to calculate the infrared spectroscopy of the...