化学学报 ›› 2011, Vol. 69 ›› Issue (10): 1141-1150.    下一篇

研究论文

NH4+( (H2O)n(n=1~9)的量子化学和ABEEM/MM的理论研究

赵飞耀, 刘翠, 宫利东*, 杨忠志   

  1. (辽宁师范大学化学化工学院 大连 116029)
  • 投稿日期:2010-12-07 修回日期:2011-01-07 发布日期:2011-01-30
  • 通讯作者: 宫利东 E-mail:gongjw@lnnu.edu.cn
  • 基金资助:

    国家自然科学基金;国家自然科学基金;国家自然科学基金;辽宁省教育厅创新团队项目

Theoretical Studies on NH4+(H2O)n(n=1~9) in terms of Quantum Chemistry and ABEEM/MM

ZHAO Fei-Yao, LIU Cui, GONG Li-Dong, YANG Zhong-Zhi   

  1. (School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029)
  • Received:2010-12-07 Revised:2011-01-07 Published:2011-01-30
  • Supported by:

    ;the National Natural Science Foundation of China

运用量子化学和ABEEM/MM浮动电荷分子力场, 构建描述铵离子-水体系相互作用的精密势能函数, 对 - (H2O)n (n=1~9)簇合物的结构和稳定性等性质进行了研究. 对团簇的结合能和电荷布居分析发现, 当n≤4时, 随着水分子数目的增加, 与水分子间尽可能多地形成线型氢键, 直至水分子在 周围形成完整的第一水合层|当n≥5时, 簇合物以 为中心, 通过氢键网络形成的环状和笼状结构为最稳定. 与第一水合层水分子的相互作用强于水分子之间的相互作用. 结果表明, ABEEM/MM方法的结果与量子化学方法得到的结果有很好的一致性.

关键词: 水合铵离子团簇, 量子化学计算, ABEEM/MM模型, 可极化分子力场, 氢键

By means of quantum chemistry and the ABEEM/MM fluctuating charge force field, an accurate interaction potential function for -H2O system was constructed, and then it was applied to study the structures and stabilities of hydrated ammonium clusters (H2O)n (n=1~9). Analysis on the binding energies and charge distributions of the clusters shows that when n≤4, as the number of water molecules increases, tends to form linear hydrogen bonds as many as possible with water molecules until its first hydration shell is completely constructed. The clusters for 5~9 water molecules tend to form a ring or a cage around the central through the network of hydrogen bonds. The strength of H-bonds between and water molecules in its 1st hydration shell is stronger than that of the H-bonds between water molecules. The results of the ABEEM/MM model are well consistent with those from quantum chemistry calculations.

Key words: hydrated clusters of ammonium, quantum chemistry calculation, ABEEM/MM model, polarizable force field, hydrogen bond