一个密度功能理论基准对抗氧化剂相关性质的多
Rodrigo A Mendes1,2, Victor A S da Mata1,2, Alex Brown2
1Departamento de Química, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, 78060-900, Brazil.
Physical chemistry chemical physics : PCCP
|January 26, 2024
概括
本研究将密度功能理论方法用于计算六种多的抗氧化性质. 建议LC-PBE用于气相O-H键解离的和电离潜力.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 药用化学 医学化学
背景情况:
- 多是众所周知的抗氧化剂,具有显著的健康益处.
- 准确的计算方法对于理解它们的抗氧化机制至关重要.
- 密度函数理论 (DFT) 是用于此类研究的广泛使用的工具.
研究的目的:
- 为了对DFT计算的23个交换相关函数进行基准测试.
- 评估六种关键多的与抗氧化剂相关的特性 (O-H键解离和电离潜力).
- 为了确定最准确的DFT函数和气相和溶剂 (水,甲醇) 条件的基础集.
主要方法:
- 密度函数理论 (DFT) 的基准计算.
- 评估了24个O-H键解离 (BDEs) 和6个电离潜力 (IPs).
- 使用了23个交换相关函数和4个基础集.
- 在气相,水和甲醇中进行计算,并对DLPNO-CCSD进行校准.
主要成果:
- 对于气相O-HBDE,LC-PBE显示了最高的精度.
- 在LC-PBE,M06-2X和M05-2X中,O-H BDEs在水中的平均绝对偏差 (MADs) 最小.
- 在气相中的IP中,LC-PBE产生了最好的MAD.
- 对于水中的IP,M05-2X,M06-2X,LC-PBE和LC-ωPBE的表现最好.
结论:
- 这项研究为多抗氧化物特性提供了一个全面的DFT基准.
- 已确定LC-PBE是气相BDE和IP的可靠功能.
- 建议在水溶液和甲醇溶液中使用特定的函数来进行准确的计算.
- 这些发现将指导研究人员选择适合抗氧化剂研究的计算方法.
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