Temperature-dependent x-ray diffraction study of Pd/Cu site interchange in non-Fermi liquid UCu(4)Pd

摘要

A pair distribution function (PDF) analysis of temperature-dependent x-ray diffraction measurements from UCu(sub 4)Pd is presented. Fits to the displacement parameters u(sup 2)'s with a Debye model show better agreement with a model that includes 25 percent of the Pd atoms on 16e (Cu) sites. In addition, significant non-thermal disorder is observed in the Cu environment, in contrast to previous measurements of local order in the U-Cu pairs.