Defect energies for pure corundum and for corundum doped with transition metal ions
Defect energies for pure corundum and for corundum doped with transition metal ions
复制标题
纯刚玉和掺杂过渡金属离子的刚玉的缺陷能量
DOI：
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发表时间：
1993
期刊：
影响因子：
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通讯作者：
E. Kotomin
中科院分区：
文献类型：
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作者：
P. Jacobs;E. Kotomin
本文用CASCADE程序中的Mott-Littleton方法计算了纯铌和掺杂Mg、Mn、Fe、Co、Ni和Ti的铌的缺陷能。结果的潜在的敏感性和需要允许松弛的完美的晶体无论是通过放松的基础应变能量最小化之前，或通过校正程序进行了讨论。形成能表明，肖特基缺陷和阴离子弗伦克尔缺陷是预期在本征材料。阳离子掺杂的晶体显示出缺陷聚集，这有利于杂质的溶解。阴离子扩散的活化能与实验符合得很好，但似乎不可能用计算来合理化所有的实验输运数据。
Abstract Defect energies have been calculated for pure corundum and for corundum doped with Mg, Mn, Fe, Co, Ni and Ti using the Mott-Littleton procedure as embodied in the CASCADE code. The sensitivity of the results to the potential and the need to allow for relaxation of the perfect crystal either by relaxing basis strains before energy minimization or by a correction procedure are discussed. Formation energies indicate that both Schottky defects and anion Frenkel defects are to be expected in the intrinsic material. The cation-doped crystals display defect clustering and this facilitates solution of impurities. Activation energies for anion diffusion are in good agreement with experiment, but it seems to be impossible to rationalize all the experimental transport data with the calculations.