HNO二聚体蓝移氢键的理论研究

利用分子轨道从头算理论和密度泛函理论结合不同理论基组对于N-H…O蓝移氢键进行了详细的研究.利用标准方法和均衡校正方法对二聚体进行了几何优化,振动频率和相互作用能的计算.拓扑学和自然键轨道理论对于蓝移氢键的本质进行分析.自然键轨道(NBO)分析表明,σ*(N-H)轨道上电子密度降低是电子密度重排效应的结果.分子内电子重排、轨道再杂化和电子受体内部结构重组共同作用结果导致了N-H的振动频率大幅蓝移现象的出现.

Theoretical study of hydrogen bond blue-shift in the HNO dimer

Ab initio molecular orbital and density functional theory (DFT) in conjunction with different basis sets calculations were performed to study the N-H...O blue-shifted hydrogen bond in the HNO dimer. The geometric structures, vibrational frequencies and interaction energies were calculated by both standard and CP-corrected methods. The topological and NBO analysis were investigated the origin of N-H bond blue shift. From the NBO analysis, the decrease in the σ*(N-H) is due to the significant electron density redistribution effect. The electron density redistribution effect, rehybridizative effect and the structure re-organization are contributed to the large blue shift of the N-H stretching frequency.