异核双卤分子XY(XY=ClF,BrF,BrCl)与C_2H_2相互作用的量子化学研究

Quantum chemistry study on the interactions between XY( XY = ClF,Br F,BrCl) and acetylene

在MP2(full)水平上,采用全电子基组,对C_2H_2与XY(XY=Cl F,Br F,Br Cl)相互作用进行了研究.相互作用能在–9.2687 k J/mol至–20.8856 k J/mol之间.自然键轨道(NBO)理论分析显示复合物中电荷转移最多的是C_2H_2…Br F,为0.0319 a.u.;最小的是C_2H_2…Br Cl,为0.0164 a.u..分子中的原子(AIM)理论分析表明复合物中Y…π键的性质与氢键类似.对称匹配微扰理论(SAPT)能量分解显示三个复合物中静电能和诱导能占相互作用能的主体,二者占到总吸引能的70%以上,其中静电作用最大,占超过50%,色散作用最小.

Quantum chemical calculations have been performed to study the interactions of C2H2 with dihalogen molecules XY（XY = C1F, BrF, BrC1） at the MP2 level. In the global minima of C2H2……XY（ XY = C1F, BrF, BrC1）, the binding energies range from - 9. 2678 kJ/mol to - 20. 8856 kJ/mol. NBO theory analyses reveal that most of the charge transfer in the complex is C2H2...BrF, for 0. 0319 a. u. ; the smallest is C2H2……BrC1, for 0. 0164 a. u.. The Y……π bonds in these complexes are similar to hydrogen bond. SAPT energy decomposition shows that the electrostatic energy and the induction energy in the complexes can be the main binding energy, which accounts for more than 70% of the total attraction energy. Among them, the electrostatic effect is the lar- gest, accounting for more than 50%, and the dispersion energy is the smallest.