Electronic Structure and Phase Stability of MgO, ZnO, CdO, and Related Ternary Alloys
Electronic Structure and Phase Stability of MgO, ZnO, CdO, and Related Ternary Alloys
复制标题
DOI：
10.1103/physrevb.77.245209
复制
发表时间：
2008-06
影响因子：
3.7
通讯作者：
Youzhang Zhu;Guangde Chen;H. Ye;A. Walsh;C. Moon;S. Wei
中科院分区：
文献类型：
--
作者：
Youzhang Zhu;Guangde Chen;H. Ye;A. Walsh;C. Moon;S. Wei
在第一性原理能带结构理论中，研究了岩盐 (B1)、闪锌矿 (B3) 和纤锌矿 (B4) 晶体结构中 MgO、ZnO、CdO 和相关合金的电子结构和相稳定性；每种材料都再现了热力学稳定相。分析了能带排列和带隙变形势，显示价带最大值从 Mg 到 Zn 再到 Cd 增加。通过应用特殊的准随机结构方法探索了三元合金的形成。正如根据二元氧化物的偏好所预期的那样，B1 结构在所有 (Mg,Cd)O 成分中都是稳定的。 (Mg,Zn)O 合金在 Mg 含量高于 34% 时经历四面体到八面体的转变，与实验一致。对于 (Zn,Cd)O，预计 Cd 含量高于 62% 时会发生转变。这些结果意味着 ZnO 与 Mg (Cd) 合金化的带隙操纵将限制在 4.0 eV (1.6 eV)，同时保持主体的四面体配位。
The electronic structure and phase stability of MgO, ZnO, CdO, and related alloys in the rocksalt (B1), zincblende (B3), and wurtzite (B4) crystal structures were examined within first-principles band structure theory; the thermodynamically stable phases are reproduced for each material. The band alignment and band-gap deformation potentials were analyzed, showing an increase in the valence band maximum from Mg to Zn to Cd. Ternary alloy formation was explored through application of the special quasirandom structure method. The B1 structure is stable over all (Mg,Cd)O compositions, as expected from the preferences of the binary oxides. The (Mg,Zn)O alloy undergoes a tetrahedral to octahedral transition above 34% Mg content, in agreement with experiment. For (Zn,Cd)O, a transition is predicted above 62% Cd content. These results imply that band-gap manipulation of ZnO from alloying with Mg (Cd) will be limited to 4.0 eV (1.6 eV), while preserving the tetrahedral coordination of the host.