title: Structure and optical properties of core-shell bimetallic Ag(n)Ni(n) clusters: Comparison with pure silver and nickel clusters.
abstract: We present the structural, electronic, and optical properties of bimetallic Ag(n)Ni(n) (n<or=7) clusters investigated in the framework of the density functional theory (DFT) (DFT and time-dependent DFT). The structure of Ag(n)Ni(n) clusters is found to be governed essentially by the formation of a Ni-core surrounded by silver atoms. The cohesive energies and the ionization potentials are calculated. The UV-visible absorption spectra of bimetallic clusters are compared to those of pure silver and nickel clusters. An interpretation of spectroscopic patterns in terms of contribution from s- and d-type excitations is also given. In particular the d electrons of nickel atoms are found to play a crucial role in the optical transitions in Ni-rich systems.
authors.affiliation: Université de Lyon, F-69622 Lyon, France.
authors.forename: M
authors.initials: M
authors.lastname: Harb
authors.forename: F
authors.initials: F
authors.lastname: Rabilloud
authors.forename: D
authors.initials: D
authors.lastname: Simon