在无相辅助场量子蒙特卡洛的响应特性
Ankit Mahajan1,2, Jo S Kurian2, Joonho Lee1,3
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
The Journal of chemical physics
|November 8, 2023
概括
我们开发了一种使用自动分化 (AD) 的新方法,通过量子蒙特卡洛模拟有效计算分子性质. 这种方法显著降低了属性计算的计算成本,使复杂的模拟更容易获得.
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:
- 计算分子性质对于理解化学反应和材料行为至关重要.
- 计算响应属性的传统方法可能在计算上昂贵.
- 无相辅助场量子蒙特卡洛 (AFQMC) 是一种用于电子结构计算的强大方法.
研究的目的:
- 开发一种计算效率高的方法来计算无相AFQMC中的第一阶级响应属性.
- 评估新方法的偏差和统计效率.
- 调查自我一致性和试验轨道选择对属性计算的影响.
主要方法:
- 在无相AFQMC中应用自动区分 (AD).
- 使用AD计算减少密度矩阵.
- 基于AD的属性计算与自我一致的优化轨道和密度函数理论 (DFT) 轨道的比较.
主要成果:
- AD允许计算低密度矩阵,每个样本的计算成本与能量计算相同.
- 使用AD进行财产计算的成本预因子在数值测试中小于4.
- 用DFT优化的轨道为所选分子提供精确的二极点时刻,与自始终优化的轨道相美.
结论:
- 自动分化提供了一种高效和准确的方法来计算无相AFQMC中的第一阶级响应属性.
- 该方法显著降低了属性计算的计算开销.
- 在许多情况下,DFT轨道是属性计算的可行和高效选择,简化了计算工作流.
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