有效地实施无旋转的重新规范化的内部合约的多重引用合集群理论
Kalman Szenes1, Riya Kayal2, Kantharuban Sivalingam2
1ETH Zürich, Department of Chemistry and Applied Biosciences, Vladimir-Prelog-Weg 2 8093 Zürich, Switzerland.
The journal of physical chemistry. A
|February 3, 2026
概括
本研究介绍了一种高效的量子化学实现,用于重新规范化的内部合约多引用合集群与单元和双元 (RIC-MRCCSD). 新方法为大型分子系统提供了可观的加速度和可扩展性.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学计算化学
- 理论化学 理论化学
背景情况:
- 多引用合集群方法对于准确描述强烈相关的电子系统至关重要.
- 现有的实施方案在计算上可能是昂贵的,并且对于大分子来说具有挑战性.
研究的目的:
- 在ORCA量子化学计划中报告重新规范化内部合约多引用合集群与单双 (RIC-MRCCSD) 方法的有效实施.
- 为了提高RIC-MRCCSD的计算效率和可扩展性,用于实际应用.
主要方法:
- 将Evangelista的Wick&d方程生成器与ORCA的AGE代码生成器集成,以实现多体余数.
- 开发RIC-MRCCSD的无旋转配方,以提高对旋转轨道版本的效率.
- 利用AGE的并行代码生成来实现多核执行和加快速度.
主要成果:
- 通过无旋转配方和并行代码生成,实现了显著的效率提升.
- 在RHF-CCSD和UHF-CCSD之间证明了计算成本,即使对于大型主动空间 (例如,CAS(14,14)).
- 成功地将该方法扩展到具有CAS12,12和809轨道的维生素B12模型,展示了它对大型系统的适用性.
结论:
- 实施的RIC-MRCCSD方法为量子化学计算的效率和可扩展性提供了显著的改进.
- 该方法的性能与其他高级相关方法具有竞争力,在不需要高阶密度矩阵的情况下提供准确的结果.
- 需要对"流量"等参数进行进一步的研究,以充分优化RIC-MRCCSD理论.
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