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国家平均驱动的相似性重规范化组的结自然轨道
Chenyang Li1, Shuxian Mao1, Renke Huang2
1Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.
Journal of chemical theory and computation
|May 15, 2024
概括
我们开发了一种更快,更便宜的量子化学计算方法,使用冷自然轨道 (FNO) 方法与状态平均驱动的相似性重规范化组 (SA-DSRG). 这大大降低了复杂分子的计算成本.
科学领域:
- 量子化学 是一个量子化学.
- 计算物理 计算物理
- 理论化学 理论化学
背景情况:
- 状态平均驱动的相似性重规范化组 (SA-DSRG) 是电子结构计算的强大方法.
- 高计算成本限制了SA-DSRG在更大的系统中的应用.
- 需要有效的近似来扩大SA-DSRG的适用性.
研究的目的:
- 通过使用冷自然轨道 (FNO) 方法,提出SA-DSRG的低成本实施方案.
- 为了评估FNO-SA-DSRG方法的准确性和效率.
- 为了实现更大,更复杂的量子化学计算.
主要方法:
- 结自然轨道 (FNO) 方法用于截断虚拟自然轨道.
- 自然轨道是从SA-DSRG二阶扰动理论 (SA-DSRG-PT2) 的单体减小密度矩阵中衍生出来的.
- 对SA-DSRG哈密尔顿式应用了附加的二级校正,以恢复丢弃的相关性效应.
主要成果:
- 在FNO-SA-DSRG方法实现高精度,在垂直过渡能量低于0.01 eV的平均绝对误差为35个有机分子.
- 与传统的SA-DSRG相比,对碳的速度提升了9倍.
- FNO方法允许对超过1000个基础函数的系统进行非扰动的SA-DSRG计算,这些计算在铁芯片上证明了这一点.
结论:
- 在SA-DSRG计算中,FNO方法可显著降低计算成本.
- FNO-SA-DSRG方法保持了高精度,同时可以研究更大,更复杂的分子系统.
- 这种实施为高层次量子化学研究开辟了新的可能性.
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