Cluster expansions of alloy energetics in ternary intermetallics

Journal Article · Fri Apr 01 04:00:00 EST 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.49.8627· OSTI ID:5001622

Wolverton, C ^[1]; de Fontaine, D ^[2]

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1. Department of Physics, University of California at Berkeley and Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)
2. Department of Materials Science and Mineral Engineering, University of California and Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)

Ternary alloy energetics are examined for substitutional systems by a formal cluster expansion. In contrast to the binary-alloy problem, several distinct basis sets are possible for the ternary cluster expansion. Several of these sets of ternary basis functions are examined and compared, and relationships are derived between the expansion coefficients, or effective cluster interactions, expressed in various bases. The method of direct configurational averaging (DCA) (based on a tight-binding, linearized muffin-tin-orbital Hamiltonian) is extended to treat ternary alloy systems. Using the DCA, ternary, fcc-based effective pair and triplet interactions are computed for the Rh-V-Ti, Pd-Rh-V, and Ag-Pd-Rh systems, and convergence of the expansion is examined. By combining the cluster expansion with the results of the DCA computations, formation energies are obtained for the completely disordered state as a function of alloy composition. Both pair and triplet interactions are seen to be crucial towards obtaining quantitatively converged energetics.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5001622
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 49:13; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
665000* -- Physics of Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOY SYSTEMS
ALLOYS
CLUSTER EXPANSION
CRYSTAL MODELS
ELECTRONIC STRUCTURE
ENERGY
FORMATION FREE ENERGY
FREE ENERGY
INTERACTIONS
INTERMETALLIC COMPOUNDS
ISING MODEL
MATHEMATICAL MODELS
MUFFIN-TIN POTENTIAL
PHYSICAL PROPERTIES
POTENTIALS
SERIES EXPANSION
TERNARY ALLOY SYSTEMS
THERMODYNAMIC PROPERTIES