用递归对式合并算法构建图形合约函数
1Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.
The journal of physical chemistry. A
|November 22, 2023
概括
一个新的算法显著提高了从配置状态函数 (CSF) 系数构建高斯复合函数 (GCF) 的效率. 这种增强的方法优化了分子轨道计算的计算速度.
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.
- 理论化学是一种理论化学.
背景情况:
- 高斯复合函数 (GCF) 对于表示分子波函数至关重要.
- 从配置状态函数 (CSF) 扩展系数构建GCF的现有方法可能是计算密集的.
- 复杂的分子系统需要提高效率.
研究的目的:
- 为了呈现一个新的,更高效的实现一个递归对式合并算法用于GCF构建.
- 通过优化内存使用和减少算法复杂性来提高计算性能.
- 评估新的算法对使用不同类型的分子轨道来表示GCF波函数的有效性.
主要方法:
- 实现GCF构建的递归对式合并算法.
- 在中间合并步骤中引入预分配工作数组.
- 分析计算效率的提高和减少对分子轨道维度 (n) 的依赖.
主要成果:
- 在整体计算效率方面取得了数量级的改进.
- 从算法中减少了对分子轨道维度 (n) 的依赖.
- 证明了GCF波函数的成功表示,使用了非局部化的正规哈特里-福克轨道和局部化的分子轨道.
- 观察到非局部化轨道对于低波函数复杂性 (小平均面数,f̅) 产生较小的误差,而局部化轨道对于更高的复杂性 (更大的f̅) 则更好.
结论:
- 新的实施为GCF建设提供了实质性的性能提升.
- 该算法的效率在很大程度上独立于分子轨道维度.
- 在GCF表示中,分局和局部轨道之间的选择取决于所需的波函数复杂性和可接受的错误容忍度.
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