在二分量相对论有效势和与之匹配的基组aug-cc-pvnz-pp (n=Q,5)的基础上,结合电子相关能的完备基组外推和四阶多项式拟合,我们用含自旋轨道角动量耦合的耦合簇方法研究了Zn2和Cd2的结构和光谱常数。尽管Zn2和Cd2的自旋轨道角动量耦合效应不及Hg2的明显,但还是把自旋轨道角动量耦合放在耦合簇迭代计算中,以获得更加合理的理论结果。通过比较,理论结果与最新发表的实验结果或其他课题组的理论结果吻合得较好,因此我们的理论计算将有助于丰富对Zn2和Cd2光谱性质的认识。%The structures and spectroscopic constants of Zn2 and Cd2 were studied using the coupled-cluster theory with spin-orbit coupling based on the two-component relativistic effective core potential and matched basis sets aug-cc-pvnz-pp (n=Q, 5), combining complete basis set extrapolation of the electronic correlation energy and fourth-order polynomial fitting technique. Spin-orbit coupling was included in the post-Hartree-Fock procedure, i.e., in the coupled-cluster iteration, to obtain more reasonable results, although the spin-orbit coupling effect observed in Zn2 and Cd2 is not visible as it is in Hg2. Our theoretical results agree wel with the latest experimental values and other groups' theoretical results, and wil be helpful in understanding the spectral characteristics of these two dimers.
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