采用基于密度泛函理论的投影缀加平面波方法和广义梯度近似计算了萤石相ZrO 2及掺杂Ru形成的复合氧化物的晶体结构、电子结构、内聚能以及Bader电荷。结果表明:萤石相ZrO 2和RuO 2的点阵参数与文献报道的数值基本相符。萤石相ZrO 2中掺入Ru后,体系的晶胞形状发生微小变形且晶胞体积减小;体系由直接带隙半导体转变为间接带隙半导体,带隙从3.06 eV减小至1.03 eV。对比Ru掺杂前后ZrO 2的内聚能、态密度和Bader电荷变化发现,Ru掺杂后体系的离子性增强,共价性减弱。
The crystal structures, electronic structures, cohesive energies, and the Bader charges of fluorite ZrO2 and Ru-doped ZrO 2 composite oxide were investigated by using projector augmented wave method and the generalized gradient approximation based on density functional theory. The results show that the calculated equilibrium lattice parameters of cubic ZrO2 and RuO2 are in good agreement with the available literatures. By adding Ru into fluorite ZrO2, the cell shape changes slightly and cell volume is reduced, the system changes from direct-band-gap semiconductor to indirect-band-gap semiconductor, and the forbidden gap width is reduced from 3.6 eV to 1.03 eV. Comparing the changes of cohesive energy, density of states and Bader charges of ZrO 2 before and after doping shows that the ionic character is enhanced and the covalent character is weakened by adding Ru into fluorite ZrO2.