X标志着点:从连续量子蒙特卡洛数据的交叉推断中得到的精确能量
Seyed Mohammadreza Hosseini1, Ali Alavi1,2, Pablo López Ríos1
1Max-Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany.
The Journal of chemical physics
|May 15, 2024
概括
本研究介绍了一种准确的推断方法,用于计算使用变量和扩散量子蒙特卡洛的分子能量. 该技术可实现对各种分子的基准质量结果,具有小的配置相互作用扩张.
科学领域:
- 量子化学是一种量子化学.
- 计算物理学的计算物理.
背景情况:
- 量子蒙特卡洛 (QMC) 方法,包括变量 (VMC) 和扩散 (DMC) 方法,是电子结构计算的强大工具.
- 准确地确定总和相对能量对于理解分子特性和化学反应至关重要.
- 现有的QMC方法在实现化学准确性方面可能面临挑战,尤其是在有限的计算资源的情况下.
研究的目的:
- 开发和验证一个准确的推断方法,从VMC和DMC计算中获得总和相对能量.
- 用小配置交互 (CI) 波函数来评估方法的有效性.
- 证明该方法能够为各种分子系统产生基准质量的能量.
主要方法:
- 在VMC和DMC能量计算中应用推断方法.
- 使用由小CI扩展组成的试验波函数,通过Jastrow因子和可选的回流转换重新优化.
- 使用非回流VMC和回流DMC能量的二次推算.
- 实施准随机波动的适当统计处理.
主要成果:
- 发现VMC和DMC能量是CI波函数平方系数的平滑函数.
- 在确切的总能量的不确定性范围内交叉的能量的二次推算.
- 该方法与C2,N2,CO2和H2O分子的基准质量的能量达成一致.
- 即使在C2分子的兴奋状态下,也得到了准确的结果.
- 这种方法在小CI扩张尺寸上被证明是有效的.
结论:
- 提议的推断方法从VMC和DMC计算中提供了非常准确的总和相对能量.
- 该技术强大可靠,为各种分子系统实现了基准准确性.
- 这种方法提供了一个计算高效的途径,以获得高精度的量子化学结果.
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