Sn-n (n = 34-44) clusters were studied using a combined method of the genetic algorithm/tight-binding search and the DFT-PBEPBE calculations. Sn-n (n = 34-44) clusters are shown to favor an assembly motif composed of small stable Sn-9 and Sn-10 subunits which are connected by cohesive linkages of smaller clusters (Sn1-5). Sn-n (n = 34-44) clusters were found to transform from a prolate pattern for Sn-34,Sn-35 to a 'Y' pattern for Sn36-39 to a plate motif for Sn40-44. Obvious structural transitions would easily occur at the cross points of binding energy curves when isomers become competitive. (C) 2012 Elsevier B.V. All rights reserved.