1,2,4-三氮杂苯-(H2O)n复合物氢键相互作用的密度泛函理论研究

用密度泛函理论方法在B3LYP/6-31++G**水平上对1,2,4-三氮杂苯-(H₂O)_n (n＝1, 2, 3)氢键复合物的基态进行了结构优化和能量计算, 结果表明复合物之间存在较强的氢键作用, 所有稳定复合物结构中形成一个N…H—O氢键并终止于弱O…H—C氢键的氢键水链的构型最稳定. 同时, 用含时密度泛函理论方法(TD-DFT)在TD-B3LYP/6-31++G**水平上计算了1,2,4-三氮杂苯单体及其氢键复合物的单重态第一¹(n, π^*)垂直激发能.

Density Functional Theory Study on Hydrogen Bonding Interaction of 1,2,4-Triazine-(H2O)n

Direct density functional theory B3LYP was employed to obtain the optimized geometries of the ground state for 1,2,4-triazine-(H₂O)_n (n＝1, 2, 3) complexes. All calculations indicate that the 1,2,4- triazine-water complexes on the ground state have strong hydrogen bonding interaction, and the structure having an N…H—O hydrogen bond and a chain of water molecules, which is terminated by an O…H—C hydrogen bond, is most stable. The first singlet (n, π^*) vertical excitation energy of the monomer 1,2,4-triazine and the hydrogen bonding complexes between 1,2,4-triazine and water has been investigated by time-dependent density functional theory.