使用直角虚拟轨道的单个值的局部第二阶Møller-Plesset理论:理论,实现和评估
Zhenling Wang1,2, Abdulrahman Aldossary1, Tianyi Shi3
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
Journal of chemical theory and computation
|October 25, 2023
概括
对于二次梅勒-普莱塞特 (MP2) 理论而言,一种新的局部相关性方法提供了对相关性能量的受控近似. 这种方法为各种分子提供准确的结果,平衡精度和计算成本.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 理论化学 理论化学
背景情况:
- 标准的电子相关联方法面临着随着分子大小的增加而出现的计算缩放挑战.
- 局部相关性方法旨在通过系统地抛弃可以忽略不计的贡献来降低计算成本.
- 理想的局部方法需要一个控制精度的单一值,实现化学相同的结果.
研究的目的:
- 开发和实施第二阶级梅勒-普莱塞特 (MP2) 理论的局部相关性方法.
- 为了建立一个单一的数值值来控制对应能量的近似值.
- 评估方法在各种分子系统和基础集中的性能.
主要方法:
- 开发一个局部MP2理论,结合一个单一的,可调节的数值值.
- 使用共享内存并行性 (OpenMP) 实现,并优化内存需求.
- 测试的门从10-5到10-8和基础设置到四倍-ζ在各种分子.
主要成果:
- 当地MP2方法证明了对关联能量计算的控制精度.
- 平行实施实现了大约50%的效率,大作业有16个核心.
- 相对能量计算显示了以降低计算成本实现精度的指导.
结论:
- 开发的本地MP2方法提供了一种计算效率高的方法来准确计算相关性能量.
- 门选择至关重要,因为衍生性质需要更严格的精度门.
- 该方法提供了一个实用的工具,用于在较大的系统上进行准确的电子结构计算.
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