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Abstract: The density functional method PW91P86 with relativistic effective core potentials (RECPs) and LANL2DZ basis set has been used to investigate the possible stable geometrical configurations and relative stabilities of the lowest-lying isomers of rhodium-doped gold clusters, Au n Rh (n=1–8). Several low-lying isomers were determined. The results indicate that the ground-state Au n Rh, n=1–8, clusters have planar structures except for n=5 and 8. The stability trend of the Au n Rh clusters shows that the clusters with even numbers of atoms are more stable than the clusters with odd numbers of atoms, indicating that the Au5Rh cluster is a magic cluster with high chemical stability. [Copyright &y& Elsevier]

The ground-state structures, electronic properties and spectra of Ti n c ( n = 3–16 and c = 0, ±1) clusters have been investigated based on density functional theory (DFT) and CALYPSO structure prediction. Geometry optimizations show that the neutral, cationic and anionic titanium clusters have the same growth pattern. The pentagonal bipyramid plays an important role in the growth process. Analysis of electronic properties shows that the thermal stability of cationic and anionic clusters is greater than that of neutral cluster. The pentagonal bipyramid and icosahedron clusters have relatively high stability. Chemical activity of titanium clusters decreases with the cluster size. The preferred dissociation pathway of Ti n + clusters is the loss of a single Ti atom to form Ti n − 1 +. Optical absorption of Ti n clusters and infrared and Raman spectra of Ti n + clusters have been simulated and can be used for their structural identification. The ground states of Ti n − clusters have been determined by comparing experimental and theoretical photoelectron spectra. • The pentagonal bipyramid plays an important role in the growth process of titanium clusters • The titanium cluster with pentagonal bipyramid or icosahedron geometry is more table than other clusters. • The preferred dissociation pathway of Ti n + clusters is the loss of a single Ti atom to form Ti n − 1 +. • The ground state of anionic Ti n − clusters are identified by photoelectron spectra.s [ABSTRACT FROM AUTHOR]

Abstract: Ab initio method based on density-functional theory has been used to investigate the Au n Pd− (n=1–5) cluster anions. The possible stable geometrical configurations with their electronic states are determined, and the energy gaps between the HOMO and LUMO of the ground states are investigated. Our results show that the one excess electron is strong enough to modify the known growth pattern of the neutral Au n Pd clusters, and indicate that the larger is the Au n Pd cluster, the smaller are the distortions by the one excess electron. [Copyright &y& Elsevier]