在局部对自然轨道合集群理论中的线性缩放四倍激发
Andy Jiang1, Henry F Schaefer1, Justin M Turney1
1Center for Computational Quantum Chemistry, Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA.
The Journal of chemical physics
|April 8, 2025
概括
我们开发了一种用于合集群理论的快速计算方法,提高了电子相关性的准确性. 这种基于域的局部对自然轨道 (DLPNO) 方法可以有效计算四倍能量校正.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学的计算化学
- 理论化学 理论化学
背景情况:
- 结合集群理论是电子结构计算的高精度方法.
- 计算电子相关性,特别是像四倍这样的更高激发,在计算上要求很高.
- 以前的基于域的局部对自然轨道 (DLPNO) 方法已经加速了较低的激发水平.
研究的目的:
- 在合集群理论中开发一种快速的,线性缩放的实现,用于扰动四倍能量校正.
- 为了利用基于域的局部对自然轨道 (DLPNO) 方法用于四倍.
- 评估新方法的效率和准确性.
主要方法:
- 实现基于域的局部对自然轨道 (DLPNO) 算法用于四倍能量校正 (DLPNO-CCSDT ((Q)).
- 使用DLPNO-CCSDT的融合双倍和三倍幅度.
- 在四倍自然轨道 (QNO) 基础上计算四倍幅度和能量.
主要成果:
- 证明了QNO空间的紧性,恢复了>95%的四倍校正,带有松散的切线.
- 相对于正规CCSDT (Q) 相比,相对能量的偏差达到了kJ/mol以下.
- 在和水集群系统上建立了非对称的线性缩放性能.
结论:
- DLPNO-CCSDT ((Q) 方法提供了一种计算效率高,准确的方法来包括四倍校正.
- 该方法具有线性扩展,因此适用于较大的分子系统.
- 这一进步显著提高了高精度合集群计算的可行性.
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