基准设限 CCSD(T) 具有局部自然轨道的大分子的能量和缩小规模的基准设校正
Dávid Mester1,2,3, Péter R Nagy1,2,3, Mihály Kállay1,2,3
1Department of Physical Chemistry and Materials Science, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Muegyetem rkp. 3, H-1111 Budapest, Hungary.
Journal of chemical theory and computation
|August 29, 2024
概括
基于密度的基数组校正 (DBBSC) 与LNO-CCSD计划中的局部近似相结合,以有效计算相关性能量. 这种方法显著减少了基数不完整的错误,使其适合大规模的量子化学计算.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学计算化学
- 理论化学 理论化学
背景情况:
- 基数不完整性 (BSI) 是量子化学计算中的一个重要错误来源,特别是对于相关性能量.
- 对大型分子系统进行准确的计算,由于基础设置的局限性,因此在计算上具有很高的要求.
研究的目的:
- 开发和实施一种有效的方法来计算基于密度的基数组校正 (DBBSC) 与局部近似相结合.
- 通过减轻基数组不完整性错误来提高大规模结合集群计算的准确性.
主要方法:
- 基于密度的基数组校正 (DBBSC) 被整合到基于自然轨道的局部合集群单元和双元与扰动三元 [LNO-CCSD(T] 方案中.
- 范围分离函数被分解成局部分子轨道 (LMO) 贡献,在紧的域内进行评估.
- 用于补充辅助基数组 (CABS) 校正,使用了局部密度拟合近似值.
主要成果:
- 拟议的DBBSC-LNO-CCSD(T) 方法显著降低了BSI误差,在双ζ基数组中通常低于1kcal/mol,而在完整基数组引用中则低于1kcal/mol.
- 在三次-ζ基数组中也观察到显著的改善.
- 为了管理计算成本,采用了高效的预选技术和保守的门.
结论:
- DBBSC-LNO-CCSD (T) 方法为大规模量子化学计算提供了一种高效和强大的方法.
- 该方法有效地纠正基数不完整性错误,仅在计算时间中适度增加.
- 这一进步使得大型分子系统的计算更加准确和可行.
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