一个基于图形的算法,用于计算配置状态函数之间的任意运算符的矩阵元素
Ignacio Fdez Galván1, Mitra Rooein1, Roland Lindh1,2
1Department of Chemistry for Life Sciences, Uppsala University, P.O. Box 576, 75123 Uppsala, Sweden.
The journal of physical chemistry. A
|February 18, 2026
概括
一个新的基于图形的算法有效地计算了量子化学中的配置状态函数 (CSF) 的矩阵元素. 这种方法提供了机器精度,并且显著优于传统的决定性扩张技术.
科学领域:
- 量子化学 是一个量子化学.
- 计算物理 计算物理
- 理论化学 理论化学
背景情况:
- 配置状态函数 (CSF) 提供了许多电子波函数的紧表示.
- 在量子化学方法中,评估CSF的矩阵元素在计算上具有挑战性.
- 现有的方法通常依赖于显式的斯莱特决定性扩展,这可能是低效的.
研究的目的:
- 开发一种新的基于图形的算法,用于在CSF之间计算矩阵元素.
- 为了克服与CSF矩阵元素评估相关的计算复杂性.
- 为各种量子化学方法提供适用的一般框架.
主要方法:
- 基于图形的表示用于编码没有明确构造的CSF扩展.
- 运算符序列直接应用于图形表示.
- 矩阵元素是通过图形穿越和重叠计算计算的.
主要成果:
- 该算法在矩阵元素计算中实现了机器级精度.
- 以图表为基础的方法表现出卓越的性能,以数量级的数量级超过了明确的决定性扩展.
- 该方法是通用的,适用于任何操作员序列.
结论:
- 开发的基于图形的算法为计算CSF矩阵元素提供了一种高效和精确的方法.
- 这一框架有助于在先进的量子化学技术中实施基于CSF的方法,例如选择和随机配置相互作用.
- 该研究提高了电子结构计算中的计算效率.
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