超越CCSD(T) 精度在较低的缩放与辅助场量子蒙特卡洛精度
Ankit Mahajan1, James H Thorpe2, Jo S Kurian3
1Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of chemical theory and computation
|February 5, 2025
概括
我们开发了一种新的量子蒙特卡洛方法,用于准确的电子结构计算. 这种方法在复杂分子的精度和效率方面超过了合集群方法.
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.
- 材料科学是一种材料科学.
背景情况:
- 精确的电子结构计算对于理解分子特性和化学反应至关重要.
- 结合集群单个和双重与扰动三重 (CCSD ((T)) 是一种广泛使用的基准方法,但计算成本昂贵.
- 配置交互单双 (CISD) 提供了一个更简单的近似,但往往缺乏足够的准确性.
研究的目的:
- 引入一种新的黑盒子辅助场量子蒙特卡洛 (AFQMC) 方法.
- 使用CISD试验状态实现高精度的电子结构计算.
- 将准确性和计算成本与CCSDT基准进行比较.
主要方法:
- 开发一个黑盒子辅助场量子蒙特卡罗 (AFQMC) 方法.
- 使用配置交互单双 (CISD) 作为试验波函数.
- 对具有挑战性的主要组和过渡金属含有分子进行计算.
主要成果:
- 该AFQMC方法总是产生比CCSD更准确的能源估计.
- 计算成本尺度为O ((N ^ 6),这比CCSD的O ((N ^ 7) 缩放更有利.
- 在复杂的分子系统,包括那些有过渡金属的准确性.
结论:
- 拟议的AFQMC方法为电子结构计算提供了一个更准确,更高效的CCSD替代方案.
- 这一进步对理论化学和材料科学有重大影响,使得研究更大,更复杂的系统成为可能.
- 该方法的黑盒性质和改进的缩放使高精度量子化学更容易获得.
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