An optimization strategy combining global semi-empirical quantum mechanical search with all-electron density functional theory was adopted to determine the lowest energy structure of (InSb)(n) clusters with n = 6-10. A new structural growth pattern of the clusters was observed. The lowest energy structures of (InSb)(6) and (InSb)(8) were different from that of previously reported results. Competition existed between core-shell and cage-like structures of (InSb)(8). The structural transition of (InSb)(n) clusters occurred at size n = 8-9. For (InSb)(9) and (InSb)(10) clusters, core-shell structure were more energetically favorable than the cage. The corresponding electronic, properties were investigated. (C) 2016 Elsevier B.V. All rights reserved.