Static correlations of higher order and diffusion in an interacting lattice gas

Journal Article · Sat Feb 01 04:00:00 EST 1986 · J. Stat. Phys.; (United States)

DOI:https://doi.org/10.1007/BF01127727· OSTI ID:6910781

Frobose, K; Jackle, J

For a lattice gas with extended hard core interaction on a square lattice the static correlation functions of higher order, which determine the average jump rate in the diffusion process, are calculated both by the Monte Carlo method and by analytic approximations. It is found that the superposition approximation is very inaccurate for the correlation functions of third and fourth order but gives better results for the average jump rate. Up to concentrations of c=0.3 better consistency with the Monte Carlo data for both quantities is obtained by treating the site occupation numbers as Gaussian random variables and accordingly expressign the correlation functions of higher order by products of averages of two particle correlations. For concentrations c greater than 0.3, however, a Bethe-Peierls cluster approximation is superior to the superposition approximation.

• Research Organization: Univ. Konstanz, Konstanz
• OSTI ID: 6910781
• Journal Information: J. Stat. Phys.; (United States), Journal Name: J. Stat. Phys.; (United States) Vol. 42:3; ISSN JSTPB
• Country of Publication: United States
• Language: English

Related Subjects

657002* -- Theoretical & Mathematical Physics-- Classical & Quantum Mechanics
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHARGED PARTICLES
CHARGED-PARTICLE TRANSPORT THEORY
CORRELATION FUNCTIONS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DIFFUSION
FLUIDS
FUNCTIONS
GASES
GAUSSIAN PROCESSES
INTERACTIONS
MATHEMATICAL MODELS
MECHANICS
MONTE CARLO METHOD
OCCUPATION NUMBER
PARTICLE INTERACTIONS
PARTICLE MODELS
QUANTUM MECHANICS
RANDOMNESS
STATISTICAL MECHANICS
TRANSPORT THEORY