评估近似密度函数理论对95个实验性特征Fe(II) 旋转交叉复合体的性能
Vyshnavi Vennelakanti1,2, Michael G Taylor1, Aditya Nandy1,2
1Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
The Journal of chemical physics
|July 11, 2023
概括
本研究评估了30个密度函数理论 (DFT) 函数,用于预测95个铁 (II) 复合体中的旋转交叉 (SCO) 行为. 三个函数 (修改后的B3LYP,M06-L,TPSSh) 准确地预测SCO,突出的是DFT.
科学领域:
- 计算化学和材料科学.
- 研究过渡金属复合体中的旋转交叉 (SCO) 现象.
背景情况:
- 旋转交叉 (SCO) 复合物,特别是Fe (II) 化合物,对于分子电子学至关重要,但对计算设计具有挑战性.
- 准确预测SCO行为需要仔细选择计算方法,特别是密度函数理论 (DFT) 函数.
研究的目的:
- 评估30个跨"雅各布梯子"的DFT函数的性能,用于预测Fe (II) 复合体中的旋转交叉.
- 确定最佳的DFT函数来建模SCO属性,并了解Hartree-Fock交换分数 (aHF) 的影响.
主要方法:
- 策划了95 Fe (II) SCO复合体的数据集 (SCO-95),并提供了低温和高温晶体结构.
- 使用30个函数的DFT计算,包括B3LYP的变化,以计算电子和吉布斯自由能量.
- 分析了变化的aHF对结构和电子性能的影响.
主要成果:
- 确定了三种表现最好的功能:修改的B3LYP (aHF=0.10),M06-L和TPSSh,准确地预测大多数复杂物中的SCO.
- MN15-L表现不佳,可能是由于参数化差异.
- 发现具有高aHF值的双混合函数不准确地稳定高旋转状态.
结论:
- SCO-95数据集为开发和验证SCO材料的DFT方法提供了一个基准.
- 当前的DFT方法,即使是准确的方法,由于忽视了晶体包装和反离子效应,与实验T1/2值的相关性有限.
- 需要进一步开发方法来纳入这些因素,以便准确预测SCO现象,如歇斯底里.
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