Geometric structures and dipole moments of Pbn (n = 13-18) clusters from ab initio quantum-chemical calculations

The lowest-energy structures and low-lying isomers of Pbn (n = 13-18) clusters are obtained by using MP2 method. In the considered configuration and size range, it is found that the lowest-energy structures of Pbn clusters favor compact structures, which is different from the prolate structures of Snn clusters at the same size range. For the lowest-energy structures, our calculated dipole moments indicate that the Pb14 and Pb18 clusters possess large dipole moments, which are in good agreement with available experiment.