New low symmetry low energy structures of 11-atom bare germanium clusters: A density functional theory study

The previously reported density functional theory (DFT) calculations at the hybrid B3LYP level on 11-vertex germanium clusters Ge-11(z) (z = -2, 0, +2, +4) have been extended to less symmetrical structures starting from lower symmetry (C-s or C-2v) structures. In addition, normal modes of imaginary vibrational frequencies less than 100 cm(-1) were followed that had been ignored in previous work. No new global minima were found for Ge-11(2-) and Ge-11(4+) However, new structures with little or no symmetry obeying the Wade-Mingos rules were found for Ge-11 and Ge-11(2+) having lower energies than any of the previously reported structures. Thus the new global minima for Ge-11 and Ge-11(2+) were found to be a C-s capped [10]-deltahedron (3,4,4-tricapped square antiprism) and a C-1 bicapped [9]-deltahedron, respectively. (c) 2006 Elsevier B.V. All rights reserved.