在ab initio DZP水平上,用能量梯度法对Li_3Al的三种几何构型进行了优化,并对其中两个能量较低的构型用单、双激发组态相互作用(CISD)进行了垂直跃迁能和振子强度计算,结果表明:Li_3Al(C_(2v))中存在着三个强度较大的跃迁,分别是从基态跃迁到1~lB_1,2~lB_1,5~lA_1,态.Li_3Al(D_(3h))中存在着四个强度较大的跃迁,分别是从基态跃迁到1~lB_2,~lA_1,3~lB_2,3~lA_1态.这些强度较大的跃迁均为粒子穴跃迁. At the ab initio DZP level, the three geometric configurations of Li 3 Al were optimized by energy gradient method, and the vertical transitions were performed on two of the two lower energy configurations using single and double excitation configuration interaction (CISD) The results show that there are three strong transitions in Li 3 Al (C 2v): transition from ground state to 1 ~ 1 B 1, 2 ~ 1 B 1, 5 ~ 1 A 1, (3h)), there are four strong transitions, from the ground state to 1 ~ 1B_2, -1A_1, 3 ~ 1B_2, 3 ~ 1A_1 state, respectively.