重新规范化的内部合同的多重引用合集群与扰乱的三倍数
Robin Feldmann1, Markus Reiher1
1Department of Chemistry and Applied Biosciences, ETH Zürich,, Vladimir-Prelog-Weg 2, 8093 Zürich, Switzerland.
Journal of chemical theory and computation
|August 19, 2024
概括
本研究引入了重新规范化的内部合约多引用合集群 (ric-MRCC) 方法,结合了DSRG和ic-MRCC理论. 新方法为复杂的分子系统提供了准确的计算,并提高了计算效率.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学的计算化学
- 理论化学 理论化学
背景情况:
- 驱动相似性重规范化组 (DSRG) 提供了一个单元的多引用合集群理论.
- 在合集群方法中可能会出现数值不稳定性.
- 对于强烈相关的系统,准确的计算仍然是一个挑战.
研究的目的:
- 为准确的电子结构计算开发一种新的计算方法.
- 为了更广泛的适用性,将DSRG方法扩展到非单元转换.
- 为了提高多引用合集群计算的效率.
主要方法:
- 结合内部合约的多引用合集群 (ic-MRCC) 与驱动相似性重规范化组 (DSRG).
- 为非单元变换调整了单元流量方程方法,创建了重新规范化的ic-MRCC (ric-MRCC) 方法.
- 介绍了贝克-坎贝尔-豪斯多夫扩张的近似值和 ric-MRCCSD[T] 的近似扰动三倍值.
主要成果:
- 证明了 ric-MRCC 方法对 H8,F2,H2O,N2 和 Cr2.2 的潜在能量曲线的准确性.
- 实现了与先进的多参考方法相提并论的准确性.
- ric-MRCCSD和 ric-MRCCSD[T]匹配了CCSD (T) 和光谱常数和能量的完全配置相互作用结果.
结论:
- 开发的重新规范化的ic-MRCC (ric-MRCC) 方法为电子结构计算提供了计算效率高,准确的方法.
- 这种方法有效地解决了多引用系统中的挑战.
- 这些发现为量子化学中更可靠的预测铺平了道路.
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