中文摘要：

Theoretical investigation of low-lying electronic states and B 3Σu-X3Σg- transition properties of selenium dimer using size-extensivity singly and doubly excitation multireference configuration interaction theory with nonrelativistic all-electron basis set and relativistic effective core potential plus its split valence basis set is presented in this paper. The spectroscopic constants of ten low-lying Λ-S bound states have been obtained and compared with experiments. Spin-orbit calculations for coupling between B3Σu- sates and repulsive 1Πu,5Πu states have been made to interpret the predissociation mechanisms of the B3Σu- state. The lifetimes of B3Σu-(ν=0～6) have been calculated with scalar relativistic effects included or excluded,respectively,and reasonably agree with experimental values.

英文摘要：

Theoretical investigation of low-lying electronic states and B3~u B3∑u^-X3∑g^-transition properties of selenium dimer using size-extensivity singly and doubly excitation multireference configuration interaction theory with nonrelativistic all-electron basis set and relativistic effective core potential plus its split valence basis set is presented in this paper. The spectroscopic constants of ten low-lying A-S bound states have been obtained and compared with experiments. Spin-orbit calculations for coupling between B3∑u^ sates and repulsive 1Лu, 5Лu states have been made to interpret the predissociation mechanisms of the B3∑u^- state. The lifetimes of B3∑u^-（v= 0 - 6） have been calculated with scalar relativistic effects included or excluded, respectively, and reasonably agree with experimental values.