Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (10): 2793-2800.doi: 10.3866/PKU.WHXB20101009

• QUANTUM CHEMISTRY AND COMPUTATION CHEMISTRY • Previous Articles     Next Articles

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).

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