title: Enhanced diffusion in finite-size simulations of a fragile diatomic glass former.
abstract: Using molecular dynamics simulations we investigate the finite-size dependence of the dynamical properties of a diatomic supercooled liquid. The simplicity of the molecule permits us to access the microsecond time scale. We find that the relaxation time decreases simultaneously with the strength of cooperative motions when the size of the system decreases. While the decrease of the cooperative motions is in agreement with previous studies, the decrease of the relaxation time opposes what has been reported to date in monatomic glass formers and in silica. This result suggests the presence of different competing physical mechanisms in the relaxation process. For very small box sizes the relaxation times behavior reverses itself and increases strongly when the box size decreases, thus leading to a nonmonotonic behavior. This result is in qualitative agreement with defect and facilitation theories.
authors.affiliation: Laboratoire de Photonique d'Angers EA 4464, University of Angers, Physics Department, 2 Bd Lavoisier, 49045 Angers, France.|University of Monastir, Physics Department, Monastir, Tunisia.
authors.forename: Sonia
authors.initials: S
authors.lastname: Taamalli
authors.affiliation: Laboratoire de Photonique d'Angers EA 4464, University of Angers, Physics Department, 2 Bd Lavoisier, 49045 Angers, France.|Appalachian State University, Physics department, Boone, North Carolina, USA.
authors.forename: Julia
authors.initials: J
authors.lastname: Hinds
authors.affiliation: Laboratoire de Photonique d'Angers EA 4464, University of Angers, Physics Department, 2 Bd Lavoisier, 49045 Angers, France.|Appalachian State University, Physics department, Boone, North Carolina, USA.
authors.forename: Samuel
authors.initials: S
authors.lastname: Migirditch
authors.affiliation: Laboratoire de Photonique d'Angers EA 4464, University of Angers, Physics Department, 2 Bd Lavoisier, 49045 Angers, France.
authors.forename: Victor
authors.initials: V
authors.lastname: Teboul