Ab initio study of AunIr (n = 1–8) clusters

The density functional method PW91P86 with relativistic effective core potentials (RECP) and LANL2DZ basis set have been used to investigate the possible stable geometrical configurations and relative stabilities of the lowest-lying isomers of iridium-doped gold clusters, AunIr (n = 1–8). Several low-lying isomers were determined. The results indicate that the ground-state AunIr, n = 1–8, clusters have planar structures except for n = 7. The stability trend of the AunIr clusters shows that even-numbered AunIr clusters are relatively more stable than the neighbouring odd-numbered ones, and indicating the Au2Ir clusters are magic cluster with high chemical stability.