中文摘要：

采用基于密度泛函理论的赝势平面波方法研究了金属元素Mg掺杂GaN的结构及电子结构性质．计算金属Mg分别替换Ga和N原子后体系的结合能，得到Mg原子更容易替换Ga原子，与他人的结果一致．掺杂后晶格常数口和f反而略有增大，并且高压下的情况是类似的．Mg掺杂后GaN电子结构显示掺杂使得GaN带隙略有增加，压强从0增加到20GPa，掺杂前后带隙值分别增大约39．1％和38．4％．

英文摘要：

The structure and electronic structure properties of GaN doped with Mg are studied by plane- wave pseudopotential density functional theory method. By calculating the binding energy of systems with Mg replacing the Ga and N atoms respectively, it is easier for Mg atoms to replace the Ga atoms, which is consistent with the results of others. The lattice constants a and c are slightly increased after doping, and the case under high pressure is similar. With the pressure increasing from 0 to 20 GPa, the band gaps of the GaN and the doped-GaN increase by about 39.1% and 38.4%, respectively.