三维过渡金属离子的切莱特复合体――电子结构方法的挑战?
Lukas Hehn1, Peter Deglmann2, Michael Kühn1
1Next Generation Computing, BASF SE, Pfalzgrafenstr. 1, 67061 Ludwigshafen, Germany.
Journal of chemical theory and computation
|May 28, 2024
概括
本研究评估了电子结构方法来预测酸 (NTA) 的特性. 合集群 (CC) 和其他先进的方法准确地预测金属离子选择性和自旋状态,优于密度函数理论 (DFT).
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:
- 亚酸 (NTA) 是一个工业上重要的化剂.
- 准确预测NTA与过渡金属的相互作用对其应用至关重要.
- 评估各种电子结构方法对于可靠的计算预测是必要的.
研究的目的:
- 评估各种电子结构方法在预测NTA对过渡金属离子的选择性方面的准确性.
- 评估这些方法在确定NTA-Fe (III) 复合物的自旋状态能量学方面的性能.
- 为了确定这些属性的最可靠的计算方法.
主要方法:
- 研究的方法包括密度函数理论 (DFT),随机阶段近似 (RPA),合集群 (CC) 理论,辅助场量子蒙特卡罗 (AFQMC),完整的活性空间自相一致场 (CASSCF),N电子价值状态扰乱理论 (NEVPT2) 和多配置对密度函数理论 (MC-PDFT).
- 探索不同的活跃空间选择策略.
- 在大型活动空间中使用密度矩阵重规范化组 (DMRG).
主要成果:
- 大多数方法对NTA的选择性与实验数据有很好的一致性,特别是对于高旋转过渡金属复合物.
- 结合集群 (CC) 方法提供了最高的准确性,其次是范围分离的DFT和AFQMC.
- 预测Fe(III) 综合体的旋转状态能量更具挑战性,CC,DMRG-NEVPT2和AFQMC同意高旋转状态优先,与大多数DFT和RPA结果相反.
结论:
- 像CC理论和AFQMC这样的先进方法对于NTA选择性和旋转状态能量学是非常准确的.
- 如果使用一致的活跃空间,NEVPT2可以实现高精度.
- 标准的DFT和RPA方法难以准确预测旋转状态的能量,有时偏好不正确的低旋转状态.
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