物理化学学报 >> 2010, Vol. 26 >> Issue (10): 2793-2800.doi: 10.3866/PKU.WHXB20101009

量子化学及计算化学 上一篇    下一篇

用第一性原理方法获取周期体系中原子的部分电荷

李亚娜, 吕洋, 周立川, 陈理, 李慎敏   

  1. 大连大学, 辽宁省生物有机化学重点实验室, 辽宁 大连 116622
  • 收稿日期:2010-04-24 修回日期:2010-06-21 发布日期:2010-09-27
  • 通讯作者: 李慎敏 E-mail:shenmin@dl.cn
  • 基金资助:

    国家自然科学基金(20973027, 20633050) 和辽宁省高等学校优秀人才支持计划项目(2007R02)资助

Atomic Partial Charges for Periodic Systems from First -Principles Calculations

LI Ya-Na. Lü Yang. ZHOU Li-Chuan, CHEN Li, LI Shen-Min   

  1. Liaoning Key Laboratory of Bio -Organic Chemistry, Dalian University, Dalian 116622, Liaoning Province, P. R. China
  • Received:2010-04-24 Revised:2010-06-21 Published:2010-09-27
  • Contact: LI Shen-Min E-mail:shenmin@dl.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20973027, 20633050) and Program for Liaoning Excellent Talents inUniversity, China (2007R02).

摘要:

利用量子化学软件包Crystal 计算了立方周期性边界条件下液态水体系的静电势(ESP) 和静电场(EF). 在此基础上, 提出了一种由第一性原理方法获取周期体系中原子的部分电荷的快捷方法. 该方法把由周期性边界条件引入的平均静电势准φmean作为一个拟合参数, 通过对第一性原理静电势与Ewald 加和法静电势的最小二乘法拟合而实现. 值得说明的是, 比较静电势与静电场拟合方法, 前者的相对拟合误差仅为2%-3%, 比后者小一个数量级. 考察了四种电荷限制条件下, 静电势、静电场拟合的水分子原子部分电荷及偶极矩的分布情况.

关键词: 原子的部分电荷, 最小二乘拟合, 静电势, 静电场, Ewald 加和法

Abstract:

We calculated the electrostatic potential (ESP) and electric field (EF) of periodic liquid water systems using the quantum chemistry software package, Crystal. We proposea method to obtain atomic partial charges rapidly for periodic systems based on first-principles calculations. In this method, the average electrostatic potential φmean, which is introduced to meet the periodic boundary condition, is taken as a parameter during the least squares fitting of the ESP from first-principles calculations and used in the Ewald summation. A comparison of the two methods, i.e., ESP and EF fitting, reveals that the relative root mean-square deviation (RMS) of the former method is only 2%-3%, which is one order of magnitude smaller than that of the latter method. In addition, the distribution of the derived atomic partial charges and dipole moments for the water system are discussed using four charge restrained fits.

Key words: Atomic partial charge, Least square fitting, Electrostatic potential, Electrostatic field, Ewald summation

MSC2000: 

  • O641