在双混合动力DFT中评估DLPNO-MP2近似值
Hagen Neugebauer1, Peter Pinski2, Stefan Grimme1
1Mulliken Center for Theoretical Chemistry, Clausius Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstraße 4, D-53115 Bonn, Germany.
Journal of chemical theory and computation
|October 20, 2023
概括
基于域的局部对自然轨道 (DLPNO) 近似扩展大分子的双混合密度函数 (DH-DFT). 这种方法显著降低了能源计算和几何优化的计算成本,为复杂系统提供了准确的结果.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 理论化学 理论化学
背景情况:
- 传统的二阶Møller-Plesset理论 (MP2) 显示了不利的N^5缩放,限制了它对大分子系统的应用.
- 双混合 (DH) 密度函数提供了更高的精度,但对于大型系统来说,计算成本昂贵.
- 基于域的局部对自然轨道 (DLPNO) 近似已成功应用于合集群方法,降低了计算成本.
研究的目的:
- 评估大分子基于DLPNO的DH (DLPNO-DH) 近似的准确性.
- 为了比较DLPNO-DH方法与传统DH方法的性能.
- 调查DLPNO-DH在能源计算和几何优化方面的适用性.
主要方法:
- 将DLPNO近似扩展到MP2理论.
- 基于DLPNO的DH (DLPNO-DH) 方法的应用.
- 使用7925个热化学数据点和239个结构数据点的大数据集进行验证.
- 包括主要组和过渡金属系统.
主要成果:
- DLPNO-DH-DFT为大型分子提供精确的能量计算和几何优化.
- 与传统的DH方法相比,DLPNO近似方法大大降低了计算成本.
- 这项研究证实DLPNO-DH在100多个原子的系统中成功应用.
- 通过PNO空间外推,可以进一步减少剩余错误.
结论:
- DLPNO-DH方法为研究大型分子系统提供了计算效率高,准确的方法.
- 这种方法显著扩大了双混合密度函数在计算化学中的适用性.
- DLPNO近似是对复杂化学结构的高精度计算的关键推动因素.
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