Accession Number:

ADA258793

Title:

Effects of Surface Structure and of Embedded-Atom Pair Functionals on Adatom Diffusion on FCC Metallic Surfaces

Descriptive Note:

Final rept. Jul 1988-Jan 1992

Corporate Author:

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD

Report Date:

1992-11-01

Pagination or Media Count:

46.0

Abstract:

Rates of self-diffusion on the 100 and 110 surfaces of nickel have been calculated using variational transition state theory VTST and four different interatomic potential energy functions based on the embedded-atom method EAM. Static properties of a single nickel atom on the 111 surface, as well as on the 100 and 110 surfaces, are also presented. The embedded-atom par functionals consist of effective pairwise additive and many-body cohesive interactions parameterized to the bulk and a few defect properties of nickel. VTST calculations of surface diffusion provide parameters and diffusion coefficients for comparison with experiment and among the four EAM potentials employed. analysis of the estimated diffusion rates based on hopping mechanism and the four pair functionals reveals that diffusion will occur more readily on 111 surface and that self-diffusion on 110 surface exhibits directional anisotropy. diffusion rate variation from one par functional to another is interpreted in terms of the effective pair potentials.... Nickel, Embedded-atom- method, Surface diffusion, Variational transition state theory, Diffusion.

Subject Categories:

  • Physical Chemistry
  • Crystallography
  • Atomic and Molecular Physics and Spectroscopy
  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE