(Co,P)双掺杂MgF2电子结构和光学性质的第一性原理研究

基于密度泛函理论(DFT)的第一性原理平面波超软赝势方法,计算了纯MgF2晶体、Co掺杂MgF2晶体、P掺杂MgF2晶体和(Co,P)双掺杂MgF2晶体的电子结构和光学特性.结果表明,掺杂后的MgF2晶体发生了畸变,原子之间的键长也有所变化.(Co,P)双掺杂后,由于非金属原子p态和金属原子d态之间的轨道杂化,在MgF...

First-principles study on electronic structures and optical properties of MgF2 codoped with cobalt and phosphorus

The electronic structure and optical properties of pure,P-doped,Co-doped and(Co,P)-codoped MgF2 had been investigated by using density functional theory based on first-principles ultrasoft pseudopotential method.The calculated results show that the lattice parameters and bond length of atoms increase due to the doped of cobalt and phosphorus.Some impurity energy levels of codoped MgF2 appear in the band gap,which results in the red shift of the optical absorption edges to visible-light region,for the reason of the hybrid orbital of p states of nometal and d states of metal.These impurity energy levels can reduce the recombination rate of photoexcited carriers and improve the photocatalytic efficiency of MgF2.Compared with the other doped,the density of states peak of impurity energy levels increase apparently for the codoped MgF2,which increases the electronic transition probability from the valence band levels to impurity energy levels and from impurity energy levels to the conduction band,and improves the solar energy utilization.All of which indicating the potential applications of(Co,P)-codoped MgF2.