Si2CmN团簇的结构及稳定性的密度泛函理论研究

用密度泛函理论(DFT)的B3LYP/6-311G*方法，对Si2CmN(m=2-10)团簇的几何构型、振动频率和基态能量等性质进行了研究，讨论了化学键的特征和热力学稳定性。振动频率和振动强度被用来判断体系的基态结构。结果表明，m=2-10的团簇为线性结构，随着m的增大，团簇的自旋多重度均为2，Si原子在C与N原子形成的线性链端部成键，团簇的基态能量近似线性增大。m为偶数的Si2CmN团簇比m为奇数的更为稳定。

A density functional study of structures and stability of Si2CmN clusters

In this paper, density functional theory(DFT) B3LYP method with 6-311G* basis set has been used to investigated geometries, vibrational frequencies and ground state energies of Si2CmN(m=2-10) clusters. The character of chemical bond and thermodynamic stability of isomers has been discussed. Harmonic frequencies and infrared spectra intensity for these clusters are given in order to aid in the characterization of the ground states. The results show that Si2CmN(m=2-10) clusters form linear structure, which are doublet states. The Si atoms favor to bond at ends of C and N linear chain. The ground state energies of clusters are nearly in proportion to increased m. The stability of Si2CmN(m=2-10) clusters with even m are greater than that with odd m.