title: Ionic shell and subshell structures in aluminum and gold nanocontacts.
abstract: Conductance histograms of aluminum and gold nanocontact rupture are studied experimentally and simulated using embedded atom potentials to assess the interplay between electronic and structural properties at room temperature. Our results reveal a crossover from quantized conductance structures to crystalline faceting or geometric shell/subshell structures at 300 K. The absence of electronic shell structure in gold and aluminum is in stark contrast with the behavior of alkaline metal nanowires which emulate their cluster counterparts. Semiclassical arguments suggest why rapid dominance of ionic structures takes place, and possible nanowire architectures are proposed in consistency with both the experimental and simulated nanocontact data.
authors.affiliation: Centro de Física, Instituto Venezolano de Investigaciones Científicas, Apartado 21827, Caracas 1020A, Venezuela.
authors.forename: E
authors.initials: E
authors.lastname: Medina
authors.forename: M
authors.initials: M
authors.lastname: Díaz
authors.forename: N
authors.initials: N
authors.lastname: León
authors.forename: C
authors.initials: C
authors.lastname: Guerrero
authors.forename: A
authors.initials: A
authors.lastname: Hasmy
authors.forename: P A
authors.initials: PA
authors.lastname: Serena
authors.forename: J L
authors.initials: JL
authors.lastname: Costa-Krämer