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评估DFT方法对[Cp*Rh]催化演化过程的适用性
Aleksandr A Chamkin1, Elena S Chamkina1
1A.N.Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, Moscow, Russia.
Journal of computational chemistry
|July 25, 2024
概括
这项研究将密度函数理论 (DFT) 方法用于[Cp*Rh]复合体的进化催化. PBE0-DH-D3BJ和TPSS0-D3BJ提供了高精度,而r2SCAN-3c提供了一个更快,更不准确的选择.
科学领域:
- 计算化学计算化学
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
背景情况:
- 进化反应 (HER) 对可持续能源至关重要.
- 有机金属复合物,特别是基于[Cp*Rh]的系统,是有希望的HER催化剂.
- 准确的催化机制理论描述对于催化剂设计至关重要.
研究的目的:
- 为了对各种密度函数理论 (DFT) 方法进行基准测试,以描述由[Cp*Rh]复合体催化的进化过程.
- 评估84种密度函数和3种复合方法的性能,与高级理论基准对比.
- 确定可靠和高效的DFT方法来研究这些催化系统.
主要方法:
- 编制了一套包括26个与[Cp*Rh]催化HER相关的基本反应的综合测试集.
- 参考能量是使用高精度的DLPNO-CCSD (T) 计算与基数和PNO空间推算获得的.
- 评估了84个密度函数 (GGAs,元-GGAs,混合体,双混合体) 的性能,并进行了各种分散校正.
主要成果:
- PBE0-DH-D3BJ表现出最高的准确性,平均绝对偏差 (MAD) 为1.36 kcal/mol.
- 紧随其后的是TPSS0-D3BJ,其 MAD 值为1.60 kcal/mol.
- 低成本的r2SCAN-3c复合物方法提供了一个更快的替代方案,MAD为2.39 kcal/mol,而明尼苏达州的功能性物 (M06-L,M06,M06-2X) 的表现不佳.
结论:
- 建议使用PBE0-DH-D3BJ和TPSS0-D3BJ进行[Cp*Rh]催化进化的精确DFT研究.
- 当高精度不至关重要时,r2SCAN-3c是一个可行的,在计算上更便宜的选择.
- 某些广泛使用的DFT函数,包括明尼苏达家族,不适合这种特定的催化系统.
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