电荷不成比例的YNiO3化合物的电子,磁和光学特性,使用GGA+U方法计算
Edjan Alves da Silva1, Samuel Domenech de Candido2, Miguel Abbate3
1Instituto de Fisica, Universidade Federal do Rio Grande do Sul Av. Bento Gonçalves 9500 91501-970 Porto Alegre RS Brazil.
RSC advances
|June 10, 2024
概括
尼基酸 (YNiO3) 呈现电荷不成比例,导致具有不同电子性质的独特Ni位点. 计算显示了一个具有反铁磁排序的绝缘阶段,与实验结果一致.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 计算材料科学科学 计算材料科学
背景情况:
- 尼基酸盐 (YNiO3) 是一种具有复杂电子和磁性行为的相关氧化物材料.
- 了解电子结构,磁性和粘合之间的相互作用对于预测材料性质至关重要.
研究的目的:
- 通过第一原则计算,研究YNiO3的电子,磁性和光学特性.
- 阐明电荷不成比例现象及其对离子位点的影响.
- 为了确定YNiO3.3的磁性排序和电子带结构.
主要方法:
- 使用通用梯度近似与现场库伦相互作用 (GGA+U) 方法进行电子结构计算.
- 在2x1x2超级电池上进行了带结构和状态密度 (DOS) 计算.
- 模拟了观察到的P21/n单临床阶段和抗铁磁性排序.
主要成果:
- 证实了电荷不成比例的Ni1 (Ni3-) 和Ni2 (Ni3+) 位点具有不同的结合特征 (离子与共价).
- 计算了一个绝缘阶段,带间距约为0.5 eV.
- 预测的反铁磁顺序与Ni1的磁矩为~1.24μB,Ni2的磁矩为~0.00μB,与中子衍射数据保持一致.
结论:
- GGA+U方法准确地复制了YNiO3.3的绝缘性和反铁磁性.
- 电荷不成比例显著影响材料的电子和磁性.
- 计算的光导率与实验结果有很好的一致性.
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