| Perovskite-like organic-inorganic hybrid compound is a kind of material which has special crystal structure. That no matter how the component and structure of the organic sheet and inorganic sheet change, and how freely you can design its properties, the inorganic sheet will be sandwiched by two organic sheets in the crystal.This dissertation has taken full advantage of this property and the general crystal models of the material were constructed. The program Dmol3 and CASTEP based on the first principle were used to calculate the electronic properties of the material.There are two parts in the dissertation. The first one concentrates on the effect of the metal element on the properties of the material. In this part, the metal element Ge, Sn, Pb were taken as the research objects, and their models were constructed. The second part concentrates on the effect of the ammonium's structural change on the properties of the material. Program Dmol3 was used to calculate the distribution of the electrons in the models, and program CASTEP was used to calculate the band structure and DOS of the models.In the first part of the dissertation, it can be found that the bonds between the organic and inorganic sheets, as well as the atoms' net change in inorganic sheet was variation along with the adjustment of the metal element according to the data of the electron distribution got from the calculation. The analysis of the band structure and DOS calculated in the first part shows the forbidden band's width decreases according to the order of Pb→Ge→Sn, the band structure composed by the inorganic sheets and the chemical bonding along with the adjustment of the distortion of the inorganic sheets.In the research of the second part, the variety of the electron distribution and the band structure in different ammoniums was found.Mulliken population analysis, the relations among the DOS, the band structure and molecule orbital were widely used in the dissertation.
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