从二核[CpFe(CO) 2和单核 (Cp) 2生成的基数:密度函数理论对一个是准确的,但对两个是不准确的
Kevin P Quirion1, Roushan Prakash Singh2, Neal P Mankad2
1Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84604, United States.
The journal of physical chemistry. A
|August 22, 2025
概括
本研究评估了过渡金属复合物的计算方法. 虽然一些密度函数理论 (DFT) 方法准确地预测了双核复合物解离,但它们与DLPNO-CCSD不同的是与单核复合物碎片化作斗争.
科学领域:
- 计算化学
- 有机金属化学
- 量子化学
背景情况:
- 密度功能理论 (DFT) 对于研究过渡金属复合物至关重要.
- 现有的DFT评估主要集中在单核复合体上,忽略了双核系统.
- 精确计算双核有机金属复合物对于理解反应机制至关重要.
研究的目的:
- 评估用于计算CpFe (CO) 2基 (Fp) 的DFT和合集群方法的准确性.
- 评估这些方法对双核[CpFe (CO) ]2 (Fp2) 和单核[Cp (CO) ]2Fe (H) ] (Fp-H) 的解离能量的性能.
- 用DFT精确计算双核复合物的挑战.
主要方法:
- 使用密度函数理论 (DFT) 方法.
- 为了进行比较,使用了合集群方法,特别是DLPNO-CCSDT.
- 计算的重点是Fp2和Fp-H的碎片能量.
主要成果:
- DFT方法显示了Fp2的广泛的碎片能量.
- 低端和中端 DFT 方法和 DLPNO-CCSD (T) 在 Fp2 分离方面表现良好.
- 高端的DFT方法在FPH债券生成方面表现出显著的错误,而DLPNO-CCSD (T) 则在FP2和FPH方面提供了合理的准确性.
结论:
- 对于双核复合物解离,DFT方法具有广泛的准确性.
- 没有一种单一的DFT方法可以准确地预测双核和单核复合物解离能.
- 尽管在化学上不完美,但DLPNO-CCSD (T) 对两种解离过程都提供了平衡的准确性.
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