N掺杂SnO_2材料光电性质的第一性原理研究

First-principles study of optical and electronic properties of N-doped SnO_2

采用全电势线性缀加平面波(full potential linearized augmented plane wave method,简记为FP-LAPW)方法,基于密度泛函理论第一性原理计算分析N掺杂SnO2材料,研究了在N替代O原子和N替代Sn原子情况下的电子态密度、电荷密度分布以及光学性质.研究表明N掺杂替代Sn较之N掺杂替代O原子的带隙要宽,都宽于SnO2的本征带隙,且两种情况下N分别处于负氧化态和正氧化态,其介电函数谱也与带隙对应发生蓝移,从理论上指出了光学性质与电子结构之间的内在关系。

Using first-principles full potential linearized augmented plane wave method（FP-LAPW）,we present the isosurface of spin density,total density of states and optical properties of undoped SnO2,substitutional N for O and substitutional N for Sn in SnO2.The results show that the band gap in two kinds of N-doped SnO2 is wider than that of SnO2 eigenstate,and the imaginary part of the dielectric function makes a blue shift corresponding to the increasing band gaps.It points out the relationship between electronic structure and optical properties in theory.