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复杂的开系统的结合集群处理:单分子磁铁的情况
Maristella Alessio1,2, Garrette Pauley Paran1, Cansu Utku1
1Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium. maristella.alessio@kuleuven.be.
Physical chemistry chemical physics : PCCP
|June 5, 2024
概括
我们对过渡金属复合体评估了两种具有成本效益的合集群方法. CC2准确地预测激发状态,而 EOM-CCSD-in-DFT 在旋转轨道合和磁性特性方面表现出色.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 材料科学 材料科学 材料科学
背景情况:
- 精确计算自旋状态的能量和属性对于开放的过渡金属复合体至关重要.
- 对于复杂的系统来说,传统的高层次方法在计算上可能是昂贵的.
研究的目的:
- 评估两个具有成本效益的合集群方法的可靠性:CC2和EOM-CCSD-in-DFT.
- 为了比较它们的表现与已建立的EOM-CCSD方法用于与旋转相关的属性.
主要方法:
- 雇佣的二级近似合集群单打和双打 (CC2).
- 利用基于投影的嵌入,将运动方程合集群单双 (EOM-CCSD) 与密度函数理论 (DFT) 结合起来.
- 在Fe (II) /Fe (III) 六合水复合物和Co (II) 分子磁铁上进行测试.
主要成果:
- CC2准确地重现了EOM-CCSD激发能 (在0.05 eV范围内).
- EOM-CCSD-in-DFT在过渡轨道角矩和旋转轨道合方面表现出卓越的性能.
- EOM-CCSD-in-DFT准确地预测了Co(II) 分子磁铁的磁性,与实验数据相匹配.
结论:
- 在多配置,开放系统中,CC2对于计算状态能量是有效的.
- EOM-CCSD-in-DFT为复杂分子磁铁的自旋轨道合和磁性特性提供了一种具有成本效益的方法.
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