Neutron Scattering Studies ofY1−xUxPd3Compounds

We have performed neutron scattering measurements on two alloys of ${\mathrm{Y}}_{1-x}{\mathrm{U}}_x{\mathrm{Pd}}_3$ ( $x=0.2,0.45\mathrm{}$). Our results indicate that the $x=0.45\mathrm{}$ compound orders antiferromagnetically with a moment of 0.7 ${\mu }_B$ per U atom and a Néel temperature ( $T_N$) of 21 K. Although the $x=0.2\mathrm{}$ compound does not order above 0.2 K, critical fluctuations associated with antiferromagnetic ordering were observed on cooling from 77 to 0.2 K. The magnetic spectra for both compounds, obtained by polarized inelastic neutron scattering, were dominated by a quasielastic response close to 0 meV, suggesting a magnetic ground state.