Specific Heat of UOs2 and UOsIr

Abstract

Abstract The low temperature specific heats of C-15 structure UOs 2 and UOsIR have been measured in order to compare them with the systems NpOs 2 , a ferromagnet with T Curie = 7.9 K , and NpOsIr, newly discovered to be a spin fluctuation system with a specific heat γ of 375 mJ mol −1 K −2 . The uranium compounds, with U—U separations of 3.25 A, less than the Hill limit of 3.4 A, show normal metallic behavior, with γ ( UOs 2 ) = 20 ± 2 mJ mol −1 K −2 and γ ( UOsIr ) = 33 ± 3 mJ mol −1 K −2 .