Structural evolution of Aun (n = 29–35) clusters: A transition from hollow cage to amorphous packing

The structural evolution and competition between the hollow cage, amorphous, fcc-like and tubular structures for medium-sized Aun (n = 29–35) clusters were investigated using density functional theory combined with empirical genetic algorithm search. Aun (n = 29–32) clusters prefer the hollow cage structures. Amorphous core–shell configurations prevail over other kinds of structural motifs for Aun (n = 33–35). A transition from hollow cage to amorphous packing occurs at n = 33. The size-dependent HOMO–LUMO gap, vertical ionization potential and electron density of states were discussed to illustrate the relationship between the electronic properties and the geometry structures.

► An extensive approach to explore the potential energy surface.
► A structural transition from hollow cage to amorphous geometry occurs at the Au33.
► The electronic properties show sensitivity to hollow cage and amorphous geometry.