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Pd/Cu Site Interchange and Non-Fermi-Liquid Behavior in UCu_4Pd

C. H. Booth·D. E. MacLaughlin·R. H. Heffner·R. Chau·M. B Maple·G. H. Kwei
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Abstract

X-ray-absorption fine-structure measurements of the local structure in UCu_4Pd are described which indicate a probable lattice-disorder origin for non-Fermi-liquid behavior in this material. Short Pd-Cu distances are observed, consistent with 24 +/- 3% of the Pd atoms occupying nominally Cu sites. A "Kondo disorder" model, based on the effect on the local Kondo temperature T_K of this interchange and some additional bond-length disorder, agrees quantitatively with previous experimental susceptibility data, and therefore also with specific heat and magnetic resonance experiments.

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C. H. Booth, D. E. MacLaughlin, R. H. Heffner, R. Chau, M. B Maple, G. H. Kwei. 1998-09-23. Pd/Cu Site Interchange and Non-Fermi-Liquid Behavior in UCu_4Pd. https://doi.org/10.1103/physrevlett.81.3960

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