探索DFT热化学对铁素模型复合体[CH3S4Fe2IIIS2H]的质子化状态的高灵敏度
Victor P Vysotskiy1, Ulf Ryde1
1Department of Computational Chemistry, Lund University, Chemical Centre, SE-22100 Lund, Sweden.
The Journal of chemical physics
|April 22, 2025
概括
铁硫复合体的精确热化学需要仔细选择密度函数理论 (DFT) 方法. r2SCAN,B3LYP和B97-1函数,以及密度校正的DFT和随机相近似,显示出可靠计算的希望.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 生物物理化学 生物物理化学
背景情况:
- 密度函数理论 (DFT) 对3D过渡金属复合物的热化学对于函数中确切的交换组件非常敏感.
- 不准确的DFT方法可能会导致相对能量的显著误差 (数百kJ/mol),特别是在铁硫复合体的质子化状态.
研究的目的:
- 评估各种DFT函数的准确性,以计算 [2Fe-2S] 铁素模型复合体 ([CH3S4Fe2IIIS2H]-) 的质子化异构体的相对能量.
- 为了将DFT结果与高层次的ab initio方法比较,如合集群和量子蒙特卡罗.
主要方法:
- 使用各种DFT函数 (r2SCAN12-D4,B3LYP-D4,B97-1-D3(OP),TPSSh,O3LYP) 来计算[CH3S4Fe2IIIS2H]-复合物的四个质子化异构体的相对能量.
- 采用高层次的ab initio方法:无相辅助场量子蒙特卡罗 (AFQMC) 和合集群与单个和双重和扰动三重 (CCSD(T)).
- 通过使用r2SCAN函数在KS-CCSD电子密度和混合函数的直接随机相近似 (dRPA) 上进行密度校正的DFT.
主要成果:
- 与AFQMC和CCSDT基准相比,r2SCAN12-D4,B3LYP-D4和B97-1-D3 (OP) DFT方法表现最好.与AFQMC和CCSDT基准相比,r2SCAN12-D4,B3LYP-D4和B97-1-D3 (OP) DFT方法表现最好.
- 用r2SCAN函数进行密度校正的DFT提供了可靠的相对能量.
- 使用TPSSh,O3LYP和r2SCAN12混合函数的直接随机相近似 (dRPA) 计算也产生了准确的结果.
结论:
- 特定的DFT函数 (r2SCAN,B3LYP,B97-1) 和密度校正DFT和DRPA等方法为铁硫提供可靠的热化学.
- 这些发现指导了研究金属蛋白活性位点和相关无机复合物的适当计算方法的选择.
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