N2O…HOCl复合物结构和性质的理论研究

分别在DFT-B3LYP和MP2/6-311++G**水平上求得HOCl + N2O复合物势能面上的六种(S1, S2, S3, S4, S5和S6)和四种(S1, S2, S4和S5)构型. 频率分析表明，其中的S1和S3为过渡态，其它为稳定构型. 在复合物S3, S5 和S6中，HOCl 单体的σ*(5O-6H)作为质子供体，与N2O单体中作为质子受体的3O原子相互作用，形成氢键结构，而在氢键复合物S2中， 质子受体为N2O单体中的端1N原子；复合物S1中，HOCl分子的σ*(5O-4Cl)作为质子供体与N2O分子中的端1N原子(质子受体)相互作用，形成卤键结构，而复合物S4中的卤键结构的质子受体为N2O分子中的端3O原子. 经B3LYP/6-311++G**水平上的计算，考虑了基组重叠误差(BSSE)校正的单体间相互作用能在-1.56 ~ -8.73 kJ·mol-1之间. 采用自然键轨道理论(NBO)对两种单体间相互作用的本质进行了考查，并通过分子中原子理论(AIM)分析了复合物中氢键和卤键键鞍点处的电子密度拓扑性质.

Theoretical Study on Structures and Properties of N2O···HOCl Complexes

B3LYP/6‐311++G???? and MP2/6‐311++G???? calculations were used to analyze the interaction between hypochlorous acid (HOCl) and nitrous oxide (N₂O). The results showed that there are six and four equilibrium geometries at the B3LYP/6‐311++G???? and MP2/6‐311++G???? computational levels, respectively. The equilibrium geometries of S1 and S3 were confirmed to be transition states by analytical frequency computations, and the other equilibrium geometries as minima. Complexes of S3 , S5 and S6 use the H(6) atom of HOCl as a proton donor and the terminal O(3) atom of N₂O as an acceptor. However, S2 uses the terminal N(1) atom of N₂O as an acceptor. As for S1 and S4 , S1 uses the Cl(4) atom of HOCl as a proton donor and the terminal N(1) atom of N₂O as an acceptor; S4 uses the terminal O(3) atom of N₂O as an acceptor. Interaction energy of the complexes corrected with basis set superposition error (BSSE) lies in the range of ?1.56–?8.73 kJ·mol^?1 at the B3LYP/6‐311++G???? levels. The natural bond orbit (NBO) and atoms in molecules (AIM) theory were also applied to explain the structures and the properties of the complexes.