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运用量子化学从头算方法研究了HNO(HNS)与(HF)1≤n≤3形成的蓝移氢键.计算结果表明:在HNO体系中,氢键NH…F的形成导致NH键收缩与伸缩振动频率蓝移,且随着n增大而增大;在HNS体系中,NH键是微小蓝移的,但键长增大,n相同时,NH键蓝移比HNO体系的小很多.电子密度拓扑(AIM)分析阐明了这些分子间相互作用的氢键性质.自然键轨道(NBO)分析表明,在HNO体系中,重极化和重杂化以及分子内超共轭大幅度减小导致了NH键的蓝移;而HNS体系中NH键蓝移很小主要是由于n(S)的超共轭给予能力比n(O)小,因而对σ*(NH)电子密度的调节能力小的缘故.
The blue shift hydrogen bonding between HNO (HNS) and (HF) 1≤n≤3 was studied by using ab initio method. The calculation results show that the formation of hydrogen bond NH ... F in HNO system leads to the NH bond shrinkage and stretching The vibrational frequency is blue-shifted and increases as n increases. In the HNS system, the NH bond is slightly blue-shifted, but the bond length increases. When n is the same, the blue-shift of the NH bond is much smaller than that of the HNO system. Density Topology (AIM) analysis elucidates the hydrogen bonding properties of these intermolecular interactions. Natural Orbital Orbital (NBO) analysis shows that in the HNO system, the heavy and heavy hybridization and the significant reduction of intramolecular superconjugation result The blue shift of NH bond in HNS system is very small, which is mainly due to the fact that the superconjugation ability of n (S) is smaller than that of n (O), and therefore the ability to regulate the electron density of σ * (NH) is small The reason.