Geometric structures of Gen (n=34-39) clusters

The structures of Ge-n (n=34-39) clusters were searched by a genetic algorithm using a tight-binding interatomic potential. First-principles calculations based on density functional theory were performed to further identify the lowest-energy structures. The calculated results show that Ge-n (n=34-39) clusters favor prolate or Y-shaped three-arm structures consisting of two or three small stable clusters (Ge-6, Ge-7, Ge-9, or Ge-10) linked by a Ge-6 or Ge-9 bulk unit. The calculated results suggest the transition point from prolate to Y-shaped three-arm structures appears at Ge-35 or Ge-36. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3425995]