对于多金属系统,自动状态与大局部活跃空间的交互
Valay Agarawal1, Daniel S King1, Matthew R Hermes1
1Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States.
Journal of chemical theory and computation
|May 24, 2024
概括
本研究介绍了一种自动化框架,用于定义局部化的活跃空间自我一致场 (LASSCF) 碎片和局部化的活跃空间状态交互 (LASSI) 模型空间. 新的LASSI[r,q]方法高效地汇聚到完全活跃空间配置交互 (CASCI) 极限,状态明显减少.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学的计算化学
- 电子结构理论 电子结构理论
背景情况:
- 局部化活性空间自我一致场 (LASSCF) 方法将波函数分解为局部化的碎片.
- 局部活跃空间状态相互作用 (LASSI) 通过哈密尔顿对角化重新引入了相关性.
- 目前还不知道定义LASSCF片段和LASSI模型空间的最佳程序.
研究的目的:
- 介绍一个自动化的框架,用于探索系统的融合模型空间在LASS.
- 引入LASSI[r,q]方法,只需要用户定义的参数r和q.
- 为了证明高效的融合到完整的活跃空间配置交互 (CASCI) 极限.
主要方法:
- 开发了一个自动化框架,系统地探索LASSI的模型空间.
- 介绍了LASSI[r,q]方法,由电子跳跃 (r) 和碎片基础函数 (q) 控制.
- 当r和q接近无限时,该方法与CASCI趋同.
主要成果:
- 对三甲氧中心复合物的数值测试显示,它们与CASCI极限的高效融合.
- 与传统的CASCI相比,LASSI[r,q]需要4-10个数量级较少的状态.
- 该框架为定义 LASSI 模型空间提供了一种系统和高效的方法.
结论:
- 在电子结构计算中,LASSI[r,q]方法为CASCI提供了一个计算效率高的替代方案.
- 这种自动化框架简化了对相关系统定义模型空间的过程.
- 这种方法显著减少了准确计算所需的状态数量.
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