采用量子化学方法中的密度泛函理论B3LYP方法,在B3LYP/6-311++G(d,p)基组水平上,对直链酸(甲酸至庚酸)与单分子水形成的体系进行结构优化和频率计算,从分子水平上研究了体系的相关的结构参数、电荷分布以及结合能,运用AIM理论分析了体系的电了密度拓扑。结果表明:直链酸与水形成两个氢键,其中羧基中氢原子作为质子供体的氢键1的键能强于水的氢作为质子供体的氢键2的键能。氢键1对体系的结合能影响起主导作用。稳定构型为六元环构型。直链酸与水结合能不随碳链增长呈明显变化,在(38.7-39.7)kJ/mol之间。

Based on B3LYP method in quantum chemistry methods, the optimized structure and frequency of the system of linear chain acid (methane acid to heptoic acid) and single-molecule water was calculated using the GAUSSIAN09 at B3LYP/6-311 ++G (d, p) level. Quantum chemical simulation was used to study the structure changes, charge distribution, frequency changes and the binding energy. AIM theory was used to study the electron density of the system topology. The results show that: all the systems form two hydrogen bonds, the hydrogen 1 (the hydrogen atom in the carboxyl group as a proton donor) is stronger than the hydrogen 2 (the hydrogen atom in water as a proton donor). The hydrogen 1 plays a leading role of affecting the binding energy. Stable configuration for the system is a six-membered ring. The binding energy is in the range of (38.7 - 39.7) kJ/mol and it doesn’t change a lot with the growth of the carbon.

在MP2水平上,采用全电子基组,对C2H2与HX(X=F,Cl,Br,I)相互作用进行了研究.构型优化同时进行频率验证,得到4个T型结构的稳定复合物,相互作用能在-12.761～-7.086 kJ/mol之间.自然键轨道(NBO)与分子中的原子(AIM)理论分析表明,形成复合物分子间的电荷转移量都很少,最大仅为0.009 a.u.,作用强度与氢键类似.对称性匹配微拢理论(SAPT)能量分解数据表明,对于C2H2…HX(X=F,Cl,Br,I)体系,从F到I,静电作用逐渐减弱,色散作用逐渐增强；相互作用能中对吸引能的贡献主要为静电能和色散能,二者之和占到80％以上,诱导能所占的比例很小,卤化氢与乙炔分子间相互作用的本质为静电作用和色散作用.

The interactions of HX(X=F,Cl,Br,I) and C2H2 were investigated at the MP2 level by using all-electron basis sets.And four T-shaped stable complexes were obtained,their interaction energy between-12.761 and-7.086 kJ/mol.The natural bond orbital(NBO) and the Atoms in Molecules(AIM) analysis reveals that the intermolecular number of charge-transfer is negligible for these four complexes,the maximum is only 0.009 a.u.,and the bonds strength of these complexes is similar to hydrogen bonds.The symmetry adapted perturbation theory(SAPT) calculations were carried out to decompose the binding energy of these complexes into individual interaction energy components.The results show that the contribution electrostatic energies decrease and the dispersion energy increases on moving from HF to HI,both electrostatic and dispersive energies are over eighty percent of these interaction energies,and the induction energies are weaker.The nature of the HX(X=F,Cl,Br,I) and the C2H2 interactions is electros

采用密度泛函理论(DFT)中的B3LYP方法,研究了Cu(I)催化六氢氮杂卓衍生物偶联反应的微观反应机理.在6-31+G(d)的水平下,对反应路径中的所有反应物、中间物、过渡态和产物进行了构型优化,通过振动频率分析及内禀反应坐标(IRC)计算对过渡态进行了验证,应用自然键轨道理论(NBO)和分子中的原子理论(AIM)分析了这些物质的轨道间相互作用及成键特征.报道了可能的反应通道CuI+R1+R2→IM2→TS1→IM3→TS2→IM4→IM5→TS3→IM6→TS4→IM7→P1→P1+IM8→IM9a→TS5a→IM10a→TS6a→IM11a→IM12→TS7→IM13→TS8→IM14→TS9→IM15→P2活化能相对较低,是主要的反应通道.同时对比研究了在没有Cu(Ι)催化剂时,反应的活化能为199.01kJ/mol,而在Cu(Ι)催化下,反应活化能为176.94kJ/mol,说明了Cu(Ι)催化剂促进了反应的进行.

The mechanism of 2-Perhydroazepinone catalyzed by Cu (Ι)was studied by the density func-tional theory.The geometric configurations of reactants,intermediates,transition states and products were optimized at B3 LYP/6-3 1+G (d)level.Vibration analysis and intrinsic reaction coordinate (IRC) of the reaction were calculated.Atoms in molecules (AIM)theories and nature bond orbital (NBO)have been used to discuss orbits interaction and bond natures.The reaction mechanism is CuI+R1+R2 →IM2→TS1→IM3→TS2→IM4→IM5→TS3→IM6→TS4→IM7→P1→P1+IM8→IM9a→TS5a→IM10a→TS6 a→IM1 1 a→IM1 2→TS7→IM1 3→TS8→IM1 4→TS9→IM1 5→P2. The activation energy of the limit-ing step is 176.94 KJ/mol,but without Cu-catalyzed,it becomes 199.01 KJ/mol,indicating that Cu(Ι) promotes the reaction.