HCN及其氢加成物分子间氢键问题的量子化学研究

QUANTUM CHEMISTRY STUDY ON THE INTERMOLECULAR HYDROGEN BONDING OF HCN, H_2CNH_3 AND H_3CNH_2

采用量子化学(MNDO、CNDO/2)方法,探讨了HCN、H_2CNH和H_3CNH_2分子间的N…H-C氢键的构成。计算表明:HCN-HCN分子间氢键作用较强,支持了实验结果。HCN及其氢加成物H_2CNH、H_3CNH_2等分子间的氢键作用依次减弱,其随C≡N、C=N、C-N的差异而变化,碳氮链中氮原子的作用是构成N…H-C型氢键的一个决定性因素。

The intermolecular hydyogen bondings of HCN, H_2CNH, H_3CNH_2 are investigated by MNDO, CNDO/2 methods. Based on the experiment, the dimers of HCN, H_2CNH, H_3CNH_2 have been chozen as calculation models. The results indicate that the interomlecular hydrogen bonding can be formed between HCN-HCN, H2CNH-H2NH. The strength of the boding decreases in the order of HCN, H2CNH, H3CNH2. The atom N in the C≡N, C=N, C-N is important for the formation of the hydrogen bonding N…H.