Tight-binding coherent-potential approximation including off-diagonal disorder

Journal Article · Fri Dec 15 00:00:00 EST 1989 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.40.12196· OSTI ID:6989908

Papaconstantopoulos, D A ^[1]; Gonis, A ^[2]; Laufer, P M ^[3]

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1. Complex Systems Theory Branch, Naval Research Laboratory, Washington, D.C. 20375-5000 (USA)
2. Lawrence Livermore National Laboratory, Livermore, California 94550 (USA)
3. Physical Sciences, Inc., 635 Slaters Lane, Suite G-101, Alexandria, Virginia 22314 (USA)

We present a generalization of the tight-binding coherent-potential approximation (TB-CPA) to substitutionally disordered alloys with both diagonal and off-diagonal disorder (ODD), taking into account all relevant {ital s}, {ital p}, and {ital d}, orbitals. This generalization is based on the work of Blackman, Esterling, and Berk (Phys. Rev. B 4, 2412 (1971)) which treated ODD within a single-band model of a disordered alloy. The method is illustrated with calculations of the density of states of disordered Cu{sub 0.75}Pd{sub 0.25} alloys. We find that inclusion of ODD improves the agreement with specific-heat data, but it does not resolve a discrepancy with the results of first-principles, muffin-tin CPA calculations regarding the Pd component of the density of states.

• OSTI ID: 6989908
• Journal Information: Physical Review, B: Condensed Matter; (USA), Vol. 40:18; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

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360104* - Metals & Alloys- Physical Properties