在CCSD(T)//B3LYP方法下,研究了四原子分子[SnCN2]的势能面,发现线性异构体SnCNN具有良好的动力学稳定性.几何分析与键分析表明,该异构体包含Sn=C三重键,并可以用过渡金属络合物配合稳定来增加其稳定性.
Triply bonded compounds RE = CR' that comprise higher-row elements are known to differ significantly in chemical bonding and reactivity from those of the traditional alkyne species. So they have formed the recent hot topic of the main-group chemistry researches. Unfortunately, these triply bonded species are usually unstable in kinetics towards conversion to doubly bonded Sn= C (R)R', making their experimental study rather difficult. To our knowledge, there was only one experiment that indirectly suggested the existence of Sn= C bonding through the de-nitrogen of ArSnC (N2 )SiMe3 via spectroscopic technique. Therefore, search of kinetically stabilized Sn =-C compounds still remains a great challenge in main-group chemistry. For this sake, we report a detailed potential energy surface study on the four-atomic molecule [ SnCN2 ] at the CCSD (T)// B3LYP level. It was shown that the linear isomer SnCNN possesses good thermodynamic and kinetic stability. Structural and bonding analysis indicates that the isomer has a Sn = C triple bond. Further stabilization of the SnCNN skeleton could be realized via effective coordination by transition-metal carbonyls. Our study is expected to provide theoretical support for future experimental synthesis and characterization of the kinetically stabilized Sn = C compounds.