Cr2+: ZnS和Fe2+: ZnS光谱特性的比较研究

基于密度泛函理论和投影平面波方法,采用第一性原理对比分析了Cr2+: ZnS和Fe2+: ZnS 的电子结构和光学性能。晶体中二价掺杂离子的态密度、能带结构和几何优化由广义梯度近似的PBE描述。Cr2+: ZnS和Fe2+: ZnS的近中红外光谱表明,特征吸收来自于局域激发的d和p-d杂化轨道之间的跃迁,Fe2+: ZnS的中心跃迁能量比Cr2+: ZnS的要低,红移0.34 eV；分别制备了Cr2+: ZnS和Fe2+: ZnS晶体,并测得了Cr2+: ZnS和Fe2+: ZnS的吸收光谱,证实了Fe2+: ZnS的特征吸收峰较Cr2+: ZnS红移0.34 eV。

Comparative study on spectral characteristics of Cr2+: ZnS and Fe2+: ZnS

Based on the density functional theory and projector augmented wave (PAW) method, a comparative study on the electronic structure and absorption spectra of Cr2+: ZnS and Fe2+: ZnS were carried out. Perdew, Burke, and Ernzerhof (PBE) function was employed for band structure calculation and geometry optimization of divalent ions in crystal. Absorption spectra of Cr2+: ZnS and Fe2+: ZnS show that the characteristic absorption is caused by local excitation from d to p-d hybrid orbitals and the central transition energy in Fe2+: ZnS is lower than in the Cr2+: ZnS, with a value of 0.34 eV. Cr2+: ZnS and Fe2+: ZnS were prepared and the absorption spectra were measured. It is proved that a red shift of 0.34 eV exists in characteristic absorption peaks of Fe2+: ZnS compared to Cr2+: ZnS.