Non-Fermi-liquid scaling in U(Cu,Al)(5) compounds

We report on the electronic properties of various UCuxAl5-x. These compounds (2.9 less than or equal to x less than or equal to 3.5). These compounds crystallize in the hexagonal CaCu5 structure. For all compounds, we find that the low-temperature specific heat diverges logarithmitically, which may be taken as an indication of non-Fermi-liquid scaling in these materials. Also we find a large magnetic anisotropy in all compounds studied, and we show that the magnetic anisotropy should not be neglected in the analysis of other bulk properties. Though for some of UCuxAl5-x polycrystals non-Fermi-liquid scaling is found also in the magnetic susceptibility, comparison with single-crystal results on UCu3Al2 indicates that any temperature dependence may be due to averaging anisotropic response over all crystallographic directions.