Using multistate dynamical corrections to compute classically exact diffusion constants at arbitrary temperature

Journal Article · Wed Feb 01 04:00:00 EST 1989 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.455995· OSTI ID:6549694

Voter, A F; Doll, J D; Cohen, J M

A method is presented for computing the classically exact, surface or bulk diffusion constant of a point defect at arbitrary temperature. The thermal diffusion constant is expressed using the squared jump length averaged over all possible final states to which the atom can jump. The rate constants that weight this sum are computed using transition state theory and molecular dynamics within a recently developed many-state dynamical corrections formalism. While these rate constants are valid only in the rare-event regime (i.e., at low temperature), it is shown that for a periodic lattice of equivalent binding sites, the resulting diffusion contants is valid at any temperature for which the lattice sites remain well defined. It is thus possible to compute classically exact surface or bulk diffusion constant for an arbitrary interatomic potential, without the time scale limitations of direct molecular dynamics.

• Research Organization: Los Alamos National Laboratory, Los Alamos, New Mexico 87545
• OSTI ID: 6549694
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 90:3; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ADSORPTION
CHEMICAL REACTION KINETICS
COMPUTERIZED SIMULATION
CORRECTIONS
DEFECTS
DIFFUSION
KINETICS
MIGRATION
REACTION KINETICS
SIMULATION
SORPTION
SURFACES