对于过渡金属复合体的旋转状态的高通量选,使用旋转极化扩展紧固结合方法
Hagen Neugebauer1, Benedikt Bädorf1, Sebastian Ehlert2
1Mulliken Center for Theoretical Chemistry, University of Bonn, Bonn, Germany.
Journal of computational chemistry
|July 4, 2023
概括
新的spGFNn-xTB方法准确地选过渡金属复合体中的旋转状态. 这些旋转极化紧密结合方法为计算化学提供了快速有效的方法,提高了高旋转和低旋转状态预测的准确性.
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:
- 半经验性GFNn-xTB紧固结合方法缺乏在过渡金属复合体中区分高旋转 (HS) 和低旋转 (LS) 状态的固有准确性.
- 精确预测旋转状态对于理解和设计各种应用的过渡金属复合体至关重要.
研究的目的:
- 将半实证的GFNn-xTB方法扩展为与旋转相关的能量项 (旋转极化),以便准确有效地选旋转状态.
- 在一个全面的过渡金属复合体基准集上评估新的旋极化GFNn-xTB (spGFNn-xTB) 方法的性能.
主要方法:
- 通过在现有的GFNn-xTB框架中纳入旋转依赖的能量术语来开发旋转极化GFNn-xTB (spGFNn-xTB) 方法.
- 对spGFNn-xTB方法与DFT参考 (TPSSh-D4/def2-QZVPP) 的评估,使用新编制的90种过渡金属复合物的基准集 (TM90S).
- 将spGFNn-xTB的性能与PM6-D3H4和PM7.7等其他半实证方法进行比较.
主要成果:
- 在完整的TM90S组中,spGFN1-xTB实现了最低的平均绝对偏差 (MAD) 19.6 kcal/mol,其次是spGFN2-xTB (24.8 kcal/mol).
- 在3d过渡金属中观察到显著的改善,spGFN1-xTB产生了最小的MAD14.2kcal/mol.
- 在89%的案例中,spGFN2-xTB正确预测了旋转状态分裂的信号,在旋转状态确定方面表现出高准确度.
结论:
- spGFNn-xTB 方法是稳健且计算效率高的工具,用于在过渡金属复合体中预先选旋转状态.
- 这些方法显著提高了与原始GFNn-xTB方法相比,自旋状态预测的准确性,特别是对于3d金属.
- 开发的工作流提供了一个有前途的方法,用于计算化学和材料设计中的高通量选.
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