We have grown the uranium compound URhIn5 with the tetragonal HoCoGa5-type by the In self-flux method. In contrast to the nonmagnetic ground state of the isoelectronic analog URhGa5, URhIn5 is an antiferromagnet with antiferromagnetic transition temperature TN=98 K. The moderately large electronic specific heat coefficient γ=50 mJ/K2mol demonstrates the contribution of 5f electrons to the conduction band. On the other hand, magnetic susceptibility in the paramagnetic state roughly follows a Curie-Weiss law with a paramagnetic effective moment corresponding to a localized uranium ion. The crossover from localized to itinerant character at low temperature may occur around the characteristic temperature 150 K where the magnetic susceptibility and electrical resistivity show a marked anomaly. © 2013 American Physical Society.

Single crystals of PuGa3 have been prepared by the gallium flux method. X-ray diffraction as well as magnetization measurements show that the hexagonal phase was selectively grown among two allotropes of trigonal and hexagonal ones. Magnetization shows highly anisotropic behavior with a magnetic easy axis along the c-direction. The present behavior is discussed in comparison with other actinide-gallium systems. © 2012 The Physical Society of Japan.