论文部分内容阅读
在MP2/6-311++G(3d,3p)电子相关校正水平上,对CH3C l二聚体可能存在的几何构型进行全自由度能量梯度优化,发现有三种势能面上极小点的构型。进一步在高级电子相关校正的MP4SDTQ、CCSD(T)/6-311++G(3df,3pd)方法水平上,对其中具有平面环状C2h对称性的总能量最小的构型进行精确计算,得到CH3C l二聚体的结合能为-8.764KJ/mol。能量分解表明在分子间相互作用中色散与静电相互作用相近,色散与静电作用能分别占总吸引能的41.8%和38.1%。分析了二聚体的谐振频率,并进行了频率归属。
In the MP2 / 6-311 ++ G (3d, 3p) electronic correlation correction level, the geometry of CH3C l dimers may exist full degree of freedom energy gradient optimization, found that there are three potential minimum structure. Further, on the level of MP4SDTQ, CCSD (T) / 6-311 ++ G (3df, 3pd) method of advanced electron correlation correction, we can get the exact calculation of the configuration with the lowest total energy of plane C2z symmetry The binding energy of CH3C l dimer is -8.764 KJ / mol. Energy decomposition shows that the interaction between chromatic dispersion and electrostatic interaction is similar, the dispersion and electrostatic interaction can account for 41.8% and 38.1% of the total energy of attraction, respectively. The resonance frequency of dimer was analyzed and the frequency assignment was carried out.