Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (10): 2173-2179.doi: 10.3866/PKU.WHXB201308272

• THEORETICAL AND COMPUTATIONAL CHEMISTRY • Previous Articles     Next Articles

Towards Understanding the Origin and Nature of the Conformational Stability of Water Clusters:a Density Functional Theory and Quantum Molecular Dynamics Study

WANG You-Juan1, ZHAO Dong-Bo1, RONG Chun-Ying1, LIU Shu-Bin1,2   

  1. 1 Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) and Key Laboratory of Resource Fine-Processing and Advanced Materials of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, P. R. China;
    2 Research Computing Center, University of North Carolina, Chapel Hill, North Carolina 27599-3420, U.S.A.
  • Received:2013-06-27 Revised:2013-08-27 Published:2013-09-26
  • Contact: RONG Chun-Ying, LIU Shu-Bin E-mail:rongchunying@aliyun.com;shubin@email.unc.edu
  • Supported by:

    The project was supported by the‘XiaoXiang Scholar’Talents Foundation of Hunan Normal University, China (23040609), Hunan Provincial Innovation Foundation for Postgraduate, China (CX2012B223), and Aid Programfor Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province, China.

Abstract:

To find out what interaction dictates the molecular stability is essential, yet still controversial even for simplest molecules. Here, using water cluster as an example, we employ quantum molecular dynamics to generate a total of 185 conformations for octamer water clusters and then employ two energy partition schemes from density functional theory to pinpoint the principles governing their stability. We found that their stability is strongly correlated with steric repulsion and exchange-correlation interactions. Explanations using two different quantities are also proposed (with the correlation coefficient larger than 0.99). This work sheds light to the fundamental understanding towards the origin and nature of molecular conformational stability for water clusters and other molecular complexes formed through intermolecular interactions.

Key words: Water cluster, Quantum molecular dynamics, Density functional theory, Steric effect, Exchange-correlation energy

MSC2000: 

  • O641