Au42: an alternative icosahedral golden fullerene cage.

We present a new icosahedral gold fullerene, Au42, based on density functional theory calculations. The Au42 fullerene has a nanoscale hollow space that can hold up to 13 Au atoms. The Au42 fullerene also has a larger HOMO-LUMO gap compared to the compact-filling geometries. However, unlike the known gold fullerene Au32, the Au42 fullerene does not satisfy the 2(N + 1)2 aromatic rule and has a positive NICS value at the center of the cage. These two nanometer-sized gold fullerenes can be used as golden cages to accommodate other atoms or molecules for the purpose of studying fundamental chemistry because of their apparently dissimilar chemical characteristics, or they can be used as structural motifs to build highly stable core-shell nanoclusters or novel cluster-assembled materials.