Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (12): 2285-2293.doi: 10.3866/PKU.WHXB201510191

• THEORETICALAND COMPUTATIONAL CHEMISTRY • Previous Articles     Next Articles

Dependence of the Many-Body Interaction Strength in Water Clusters (H2O)n on the Water-Water Distance

Wei. YANG,Xiao-Lei. LI,Chang-Sheng. WANG*()   

  1. 1 School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, Liaoning Province, P. R. China
  • Received:2015-08-10 Published:2015-12-04
  • Contact: Chang-Sheng. WANG E-mail:chwangcs@lnnu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21173109);Program for Liaoning Excellent Talents in University,China(LR2012037);Program for Leading Figures in Dalian, China

Abstract:

The total interaction energies and two-, three-, and four-body interaction energies of water clusters (H2O)n (n = 8, 10, 16, 20, 22, 24) are obtained from MP2/aug-cc-pVTZ calculations including the basis set superposition error (BSSE) correction. The calculation results show that the two-body interaction energies contribute more than 70% to the total interaction energy, the three-body interaction energies contribute up to 25%, the four-body interaction energies sometimes contribute up to 3%, and other many-body interaction energies always contribute less than 0.5%. It is also found that about 99.4% of the total interaction energies can be reproduced when some special two-, three-, and four-body interactions are considered. These interactions are the two-body interactions where the distance between two water molecules is less than 0.68 nm, the three-body interactions where the nearest water-water distance among three water molecules is less than 0.31 nm, and the four-body interactions where the nearest water-water distance among four water molecules is less than 0.31 nm. Our investigation results suggest that a reliable method, aimed at modeling biosystems, should possess the ability to correctly simulate these special two-, three-, and four-body interactions.

Key words: Water cluster, Two-body interaction, Three-body interaction, Four-body interaction

MSC2000: 

  • O641