title: Structures and stabilities of small lead oxide clusters PbmOn (m=1-4,n=1-2m).
abstract: The structures and stabilities of small lead oxide clusters PbmOn with m=1-4, n=1-2m are systematically studied using density functional theory. It is found that the lowest-energy structures of all these clusters can be obtained by the sequential oxidation of small "core" lead clusters. For Pb-rich clusters (oxygen-to-lead ratio<1), oxygen atoms favor bridge sites for Pb2On and Pb3On and surface sites for Pb4On. The lead-monoxide-like clusters (PbO)i (i=1-4) have great stability because of their significant dissociation energies and highest occupied molecular orbital-lowest unoccupied molecular orbital gaps. This suggests that they could be adopted as the building blocks of cluster-assembled materials. For O-rich clusters (oxygen-to-lead ratio>1), the grouping of oxygen atoms usually appears. It is found that the structures with a grouping of more than two oxygen atoms are unstable.
authors: Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China.
authors: Haitao
authors: H
authors: Liu
authors: Shanying
authors: S
authors: Wang
authors: Gang
authors: G
authors: Zhou
authors: Jian
authors: J
authors: Wu
authors: Wenhui
authors: W
authors: Duan