Doping golden clusters: MAu−19 and M2Au−18 (M = Cu and Na)

The structural and electronic properties of MAu−19 and M2Au−18 (M = Cu and Na) have been studied by the relativistic density-functional calculations. It is found that the most stable configurations of CuAu−19 and Cu2Au−18 are the face-centered and two-face-centered doped structures based upon the tetrahedral structure Au−20. In contrast, the ground states of Na-doped gold clusters (NaAu−19 and Na2Au−18) exhibit flat-cage configurations. The PES of these ground states are depicted that may be helpful to identify their configurations in the future experiments. The face-centered and two-face-centered doped tetrahedral structures of CuAu−19 and Cu2Au−18 have a large HOMO–LUMO gap, indicating that they are chemically stable.

► The most stable CuAu−19 and Cu2Au−18 are the face-centered doped tetrahedral structures.
► The ground states NaAu−19 and Na2Au−18 exhibit flat cage configurations.
► Dopant–Au interactions and ionic radius of doping atom affect the structural property.