不同浓度C掺杂SnO2的第一性原理计算

摘要

采用基于密度泛函理论的第一性原理对不同浓度C掺杂SnO2体系的晶体结构、能带结构、态密度以及光学性质进行了计算.结果表明:掺杂C原子后,晶胞体积和晶格常数都略微增大,且随着掺杂浓度的增大而增大,能带的禁带宽度则随着浓度的增大而减小.在光学性质中,掺杂C原子后体系的光吸收边都向低能方向移动,随着掺杂浓度的增大,体系红移的幅度也增大.%The crystal structures,band structures,densities of states and optical properties of different concentra-tions C－doped SnO2 are investigated by the first－principles calculation method based on density functional the-ory.The results show that the unit cell volume and lattice constants of the doping systems are slightly increased with the increasing doping concentration.The band gap of the band decreases as the concentration increases.From the calculation of the optical properties,the absorption edge of the system after doping C moves towards the low energy direction.With the increase of doping concentration,the redshift of the system is more obvious.