跨关联合集群方法. 跨关联合集群方法. II. II. II. II. II. II. II. II. II. II. II. II. II. II. II. II. II. II. 分子系统是分子系统
Thomas Schraivogel1, Evelin Martine Christlmaier1, Pablo López Ríos1
1Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany.
The Journal of chemical physics
|June 1, 2023
概括
这项研究通过使用先进的Jastrow因子和合集群方法验证了跨相相关的哈密尔顿式,以获得准确的基态能量. 结果显示分子相对能量的基本极限准确度接近完全.
科学领域:
- 量子化学 是一个量子化学.
- 计算物理 计算物理
背景情况:
- 准确计算基态能量对于理解分子性质至关重要.
- 传统方法面临着强大的电子相关性和基础集不完整性的挑战.
研究的目的:
- 为了证明跨相关的哈密尔顿式对计算基态能量的准确性.
- 通过复杂的Jastrow因子和合集群技术来评估跨相关方法的性能.
- 为了有效地研究三体整体效应的结合.
主要方法:
- 变量蒙特卡罗 (VMC) 对于Jastrow因子.
- 结合集群 (CC) 和可区分集群 (DC) 方法,具有单个和双重激发 (CCSD).
- 跨相关汉密尔顿的应用.
主要成果:
- 以cc-pVTZ基础集的跨相关可区分集群方法 (TCDC) 在超过30个原子和分子的相对能量上实现了近乎完整的基础极限精度.
- 结果接近完全配置交互 (FCI) 的质量.
- 使用跨相关联合集群 (TCC) 方法对分子解离的研究提供了对不同相关性模式的见解.
结论:
- 跨关联的哈密尔顿数,结合VMC衍生的Jastrow因子和CC/DC方法,为电子结构计算提供了高度准确和高效的方法.
- 该TCDC方法显示出优异的收特性,接近FCI质量.
- 在没有明确计算的情况下包含三体积的有效策略在数值上是合理的.
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