物理化学学报 >> 2005, Vol. 21 >> Issue (06): 632-636.doi: 10.3866/PKU.WHXB20050611

研究论文 上一篇    下一篇

精确固定节面量子Monte Carlo差值法

黄宏新   

  1. 湖南师范大学化学化工学院, 长沙 410081
  • 收稿日期:2004-10-25 修回日期:2005-01-03 发布日期:2005-06-15
  • 通讯作者: 黄宏新 E-mail:huanghongxin@etang.com

Differential Accurate Fixed-node Quantum Monte Carlo Method

HUANG Hong-xin   

  1. College of Chemistry and Chemical Technology, Hunan Normal University, Changsha 410081
  • Received:2004-10-25 Revised:2005-01-03 Published:2005-06-15
  • Contact: HUANG Hong-xin E-mail:huanghongxin@etang.com

摘要: 提出了精确固定节面量子Monte Carlo差值法, 这个新算法能够在精确固定节面量子Monte Carlo方法的基础上直接计算两个体系之间的能量差, 且使计算结果的统计误差达到10-5 hartree 数量级, 获得电子相关能90%以上. 我们把这个新算法应用于分子势能面的研究中, 使用一个“刚性移动”模型, 利用Jacobi变换使分子两个几何构型的能量计算具有很好的正相关性, 因而能得到准确的能量差值, 由此就可以得到精确的分子势能面.

关键词: 精确固定节面量子Monte Carlo方法, 差值法, 相关取样, 势能面

Abstract: A novel quantum Monte Carlo(QMC) differential approach was proposed, which can be used to directly compute the energy difference between two systems on the basis of accurate fixednode QMC algorithm, allowing the statistical error in the order of 10-5 hartree and the electroncorrelation energy over 90% for the computation results. By using a “rigid move” model and Jacobi transformation, a good positive correlation between energies of two configurations for a molecule was obtained, and thus the acquisition of accurate energy differences and molecules’ potential energy surfaces for two investigated systems is feasible.

Key words: Accurate fixed-node quantum Monte Carlo method, Differential approach, Correlation sampling, Potential energy surface