Understuding on the stable structures of transition metal boride can provide valuable information on its properties and the preparation of new materials.The stability of each optimized structure of Sc3B2 cluster was investigated by density functional theory (DFT)Becke3LYP/Lanl2dz pseudo potential basis set.Additionally, the electron spin density distribution was analyzed by both kinetics and thermodynamics of the isomerization reaction between these structures.The following results were obtained.The peripheral and internal α and β electron spin density distribution had a certain effect on the stability of the optimized structures of Sc3B2 cluster, and the most stable structure of Sc3B2 cluster was determined to be 1(2), 2(2).The limit of isomerization was affected by the thermodynamic stability of reactants and the products.To predict the extent of cluster isomerization reactions, a linear equation of lnK=0.403 48ΔE-0.001 95 was established.

density functional theory； spin density； isomerization； kinetic stability； thermodynamic stability