在Pd和Y原子相对论有效原子实势和基函数SDD下,使用密度泛函理论B3LYP方法对PdYn±(n=0,1,2,3)分子离子的势能曲线与稳定性进行计算研究,结果表明,PdY分子和PdY-,PdY2-,PdY3-与PdY+分子离子的基态电子状态分别为X2∑、X1∑、X2∑、X1∑、X1∑,能稳定存在,势能函数可用Murrell-Sorbie函数表达,并计算得到相应的力常数与光谱数据;PdY2+和PdY3+分子离子的基态分别为X2∑和X1∑,是亚稳定态,PdY3+分子离子的三重态是排斥态,不能稳定存在. The potential energy curves and the stability of PdYn ± (n = 0, 1, 2, 3) molecular ions were calculated by B3LYP method using the relativistic effective atom real potential and the basis function SDD of Pd and Y atoms. The results The results show that the ground states of PdY, PdY-, PdY2-, PdY3- and PdY + are X2Σ, X1Σ, X2Σ, X1Σ and X1Σ, respectively. The potential energy function can be expressed by Murrell-Sorbie function And the corresponding force constants and spectral data were calculated. The ground states of PdY2 + and PdY3 + were X2Σ and X1Σ respectively, which were metastable states. The triplet state of PdY3 + ions was repulsive and could not exist stably.