分割扩展整合方案对于不受限制的第二阶级莫勒-普莱塞特扰动理论基态能量的分割扩展整合方案
Magnus Bukhave Johansen1, Andreas Erbs Hillers-Bendtsen1, Hector H Corzo2
1Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark.
The Journal of chemical physics
|January 21, 2025
概括
分解-扩展-整合 (DEC) 方法现在支持不受限制的Hartree-Fock,使大开系统能够进行线性缩放. 这个框架使用碎片优化值,准确地计算出与最小误差相关性能量.
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:
- 分割-扩展-整合 (DEC) 框架为电子结构计算提供线性缩放.
- 将DEC扩展到不受限制的Hartree-Fock引用对于准确建模开放系统至关重要.
- 大规模并行实现对于处理大型分子系统至关重要.
研究的目的:
- 扩展线性缩放 DEC 框架,包括不受限制的 Hartree-Fock (UHF) 引用.
- 评估对相关能和相对能量的扩展DEC方法的准确性.
- 评估碎片优化值 (FOT) 对计算精度和效率的影响.
主要方法:
- 在DEC框架内,轨道空间的分割和局部分子轨道的使用.
- 通过碎片优化值 (FOT) 实现错误控制.
- 在MP2理论层面的公开和封闭外系统的基准测试计算.
主要成果:
- 扩展的DEC方法保持了线性缩放,适合大规模并行计算.
- 10-3的FOT可以回收超过98%的开放外系统的完全相关性能量.
- 准确的相对能量需要10-4的更紧密的FOT,这对化学多样化的系统构成潜在的挑战.
结论:
- DEC框架的扩展到不受限制的引用保留了它对大型开放系统的线性缩放优势.
- 仔细选择FOT对于实现相关性和相对能量计算所需的准确性至关重要.
- 该方法非常适合并行实施,能够有效计算大型分子的电子性质.
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