利用B3LYP/6-311++G(d,p)方法对4-巯基吡啶及其二聚体的结构和振动光谱进行了计算,对形成二聚体后在结构和光谱上的变化及作用力做了初步分析,并对光谱做了指认.结果显示,4-巯基吡啶(4MPY)的稳定结构为Cs对称性,其二聚体是由SH基团中H原子与另一个环上的N原子靠分子间氢键形成的;相对于单体来说,二聚体形成后在结构与光谱上均有一定的变化.
The optimized molecular structure and vibrational frequencies of 4-mercaptopyridine monomer and dimer were studied by density functional theory using B3LYP method with the 6-311++G(d, p) basis set. On the basis of the calculations, the assignments of vibrational spectra were performed on monomer and dimer, and the change in structure and vibrational spectrum of dimer as well as the intermolecular force of forming dimer were investigated. It was found that the two pyridine ring planes are vertical to each other, and the dimer was formed through H-bonding, which is between the nitrogen on one ring and the hydrogen of SH moieties on another. Furthermore, the structure and vibrational spectrum of the dimer have some changes with respect to those of the monomer.