HCN分子间及HCN与HCCH、HCOH分子间氢键问题的量子化学讨论

A Quantum Chmistsy Study On The Intermolecular Hydrogen Bondings Between HCN And HCCH,HCN Or HCOH

采用量子化学(MNDO、CNDO/2)方法,探讨了 HCN 分子间及 HCN与 HCCH、HCOH 分子间的 N…H—C 氢键的构成。计算表明,HCN—HCN 分子间 N…H—C 氢键作用较强,支持了实验结果。尽管 C、N、O 的电负性依次增加,但 HCCH 和 HCOH 与 HCN 的分子间氢键作用较弱,HCN 分子间的氢键作用可能不仅与 N 原子,而且与 C≡N 键的存在有关。

The intermolecular hydrogen bondings between HCN and HCCH,HCN or HCOH are investigated by the MNDO,CNDO/2 methods.The dimers of HCN,HCN- HCCH,HCN-HCCH are proposed as the calculation models.The results indicated that the intermolecular hydrogen bonding energy gradually decreases in the order of HCN, HCCH,HCOH.The exsisting of triple bond in C≡N is important for the forming of the hydrogen bonding N…H.