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用量子化学B3LYP方法和6-31++G**基函数研究了s-四嗪-水簇复合物基态分子间相互作用,并进行了构型优化和频率计算,分别得到无虚频稳定的s-四嗪-(水)2复合物、s-四嗪-(水)3复合物和s-四嗪-(水)4复合物6个、9个和12个.复合物存在较强的氢键作用,复合物结构中形成一个N…H—O氢键并终止于O…H—C氢键的氢键水链构型最稳定.经基组重叠误差和零点振动能校正后,最稳定的1∶2,1∶3和1∶4(摩尔比)复合物的结合能分别是41.35,70.9和94.61kJ/mol.振动分析显示氢键的形成使复合物中水分子H—O键对称伸缩振动频率减小(红移).研究表明N…H键越短,N…H—O键角越接近直线,稳定化能越大,氢键作用越强.同时,用含时密度泛函理论方法在TD-B3LYP/6-31++G**水平计算了s-四嗪单体及其氢键复合物的第一1(n,π*)激发态的垂直激发能.
Quantum chemical B3LYP method and 6-31 ++ G ** basis function were used to study the ground state molecular interactions of s-tetrazine-water cluster, and the configuration optimization and frequency calculation were performed. tetrazine- (water) 2 complex, s-tetrazine- (water) 3 complex and s-tetrazine- (water) 4 complex were 6, 9 and 12. The complex was strongly H-O hydrogen bond in the complex structure and terminate in O ... H-C hydrogen bond has the most stable hydrogen bond water chain structure. After the base group overlap error and zero-point vibration energy can be corrected, The binding energies of the stable 1: 2, 1: 3 and 1: 4 (molar ratio) complexes were 41.35, 70.9 and 94.61 kJ / mol, respectively. Vibration analysis showed that the formation of hydrogen bonds caused the H- Symmetric stretching vibration frequency decreases (redshift) .Studies show that N ... H bond is shorter, N ... H-O bond angle closer to a straight line, the greater the stabilizing energy, the stronger the hydrogen bonding effect.At the same time, with the time-dependent density Functional Theory The vertical excitation energy of the first 1 (n, π *) excited state of s-tetrazine monomer and its hydrogen-bonded complex was calculated at TD-B3LYP / 6-31 ++ G ** level.