在KBF (B = Sc,Ti,Fe,Co) 中的轨道排序模式
Fabien Pascale1, Philippe D'Arco2, Sami Mustapha3
1Université de Lorraine-Nancy, CNRS, LEMTA, Nancy, France.
Journal of computational chemistry
|May 14, 2024
概括
过渡金属矿的轨道排序在不同的模式中显示出类似的能量和体积依赖性. 大多数配置即使在低温下也被占用,这表明研究更大的系统的潜力.
科学领域:
- 固态化学 固态化学
- 量子力学就是量子力学.
- 材料科学 材料科学 材料科学
背景情况:
- 过渡金属矿表现出复杂的轨道顺序 (OO) 由于部分占用d-轨道.
- 在KBF矿中B位过渡金属之间的合导致了许多可能的OO模式.
研究的目的:
- 研究KBF矿 (B = Sc,Ti,Fe,Co) 中轨道排序的量子力学行为.
- 描述各种OO模式的能源格局和结构影响.
- 在更大的超级细胞中开发轨道排序的预测模型.
主要方法:
- 使用高斯型基础集和B3LYP混合函数的量子力学计算.
- 使用40个原子的超级细胞方法来建模KBF矿.
- 将许多OO模式分为162个相当的配置类别进行分类.
主要成果:
- 所有四种KBF矿化合物都表现出类似的能量和体积依赖于OO模式.
- 不同的OO配置所占的能量很小 (每配方单位1-2mE).
- 一个基于相邻位置相对轨道顺序的线性模型准确地重现了能量顺序.
结论:
- 这些KBF矿中的大多数轨道排序配置可能在室温和低温下被占用.
- 开发的线性模型显示了研究更大,更复杂的超级细胞中轨道秩序的前景.
- 这些发现为过渡金属矿的电子和结构性质提供了洞察力.
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