定量化 内部分子基础 集合 叠加错误
Quentin Pitteloud1, Peter Wind1, Stig Rune Jensen1
1Hylleraas Centre, Department of Chemistry, UiT the Arctic University of Norway, Tromsø N-9037, Norway.
Journal of chemical theory and computation
|August 18, 2023
概括
中等大小的高斯基数组在计算化学中会导致重大错误,人工偏好紧的分子形状. 为了准确的构造分析,需要更大的基础集或多解析度方法.
科学领域:
- 计算化学是一种计算化学.
- 量子化学是一种量子化学.
- 分子建模分子建模
背景情况:
- 基础集叠加错误 (BSSE) 是量子化学计算中的一个已知的工件.
- 准确的结构分析对于理解分子性质和相互作用至关重要.
研究的目的:
- 在中型高斯基数组中量化分子内基数组叠加错误 (BSSE).
- 评估在大型分子系统中减轻BSSE的方法.
- 评估 BSSE 对形状偏好的影响.
主要方法:
- 进行了哈特里-福克 (HF) 和密度函数理论 (DFT) 的计算.
- 计算使用了中等大小的高斯基数集 (例如,偏振双色球,偏振三色球).
- 内部分子BSSE研究了一种186原子的去.
- 测试了基于多层层的两个BSSE校正程序和多重解析方法.
主要成果:
- 显著的分子内BSSE (高达~80kJ/mol) 被观察到与极化双泽塔基础集.
- 误差被减少到~10kJ/mol与极化三倍泽塔基础集.
- 需要更大的基础集 (极化四倍泽塔) 或多分辨率方法来最大限度地减少BSSE低于几kJ/mol.
- 在延伸的方面,BSSE人工稳定了紧的形状.
结论:
- 中等大小的高斯基数组引入了大量的分子内BSSE,影响了构造稳定性.
- 准确的形状预测需要更大的基础集或先进的技术,如多分辨率方法.
- 对于大型分子的可靠计算研究,必须仔细处理BSSE.
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