| 1. | After geometry optimization , their energy band structure , densities of states were calculated and analysised . we also calculated the model of doping cr , which can change the energy band structure of cdgeas2 , the result is valuable for decreasing optical absorption . through the energy analysised , it was suggested that a germanium - on - arsenic anti - site defect was the most possible defect which may be associated with the 5 . 5 micron absorption , the result of analysis are agreement with the research of epr , so the calculates are accurate 运用密度泛函理论计算,建立纯砷化锗镉晶体的结构模型并对之进行结构优化,使理论模型更加接近真实结构,从而研究纯砷化锗镉晶体的能带结构和态密度、光学性质;分别建立砷空位模型( vas - cdgeas2 ) ,锗占砷位模型( ge / as - cdgeas2 ) ,分别计算它们的能带结构、态密度、光学性质。 |