Hg. Lukefahr et al., Nuclear magnetic resonance studies of non-Fermi liquid behaviour in Y0.8UxTh0.2-xPd3 and Y0.95U0.05Pd3, PHYSICA B, 301(3-4), 2001, pp. 379-388
Y-89 NMR spectra of the non-Fermi liquid alloys Y0.8UxTh0.2-xPd3, x = 0, 0.
01, 0.025, and 0.05, exhibit resolved impurity satellites due to specific c
onfigurations of U impurities around Y sites. The strongly concentration-de
pendent satellite linewidths grow more rapidly than the satellite shifts as
temperature is reduced, indicating a distribution of characteristic temper
atures and the influence of interactions between U ions. The data suggest a
disorder-driven mechanism for non-Fermi liquid behavior in this system. Th
e concentration-independent satellite shifts from the bulk resonance are no
t proportional to the macroscopic magnetic susceptibility, suggesting an un
conventional Kondo effect. Y-89 NMR spectra of the related non-Fermi liquid
alloy Y0.95U0.05Pd3 also exhibit resolved impurity satellites, the behavio
r of which gives no indication of widely distributed characteristic tempera
tures. This suggests that ligand disorder is more important than f-sublatti
ce dilution in driving non-Fermi liquid behavior in Y0.8UxTh0.2-xPd3. (C) 2
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