title: Molecular dynamics study of oxygen diffusion in Pr(2)NiO(4+delta).
abstract: Oxygen transport in tetragonal Pr(2)NiO(4+delta) has been investigated using molecular dynamics simulations in conjunction with a set of Born model potentials. Oxygen diffusion in Pr(2)NiO(4+delta) is highly anisotropic, occurring almost entirely via an interstitialcy mechanism in the a-b plane. The calculated oxygen diffusivity has a weak dependence upon the concentration of oxygen interstitials, in agreement with experimental observations. In the temperature range 800-1500 K, the activation energy for migration varied between 0.49 and 0.64 eV depending upon the degree of hyperstoichiometry. The present results are compared to previous work on oxygen self-diffusion in related K(2)NiF(4) structure materials.
authors.affiliation: Department of Materials, Imperial College London, London, UKSW7 2AZ.
authors.forename: David
authors.initials: D
authors.lastname: Parfitt
authors.forename: Alexander
authors.initials: A
authors.lastname: Chroneos
authors.forename: John A
authors.initials: JA
authors.lastname: Kilner
authors.forename: Robin W
authors.initials: RW
authors.lastname: Grimes