Electronic properties of beryllides of the rare earth and some actinides

A magnetic study has been conducted of 17 beryllides of the form MBe₁₃, M being a rare earth, Th, U, and an alloy La0.75{Tm}0.25$. Specific-heat studies were also made for $M=La,{{0ex}{0ex}}Pr,{{0ex}{0ex}}Sm,{{0ex}{0ex}}Tm,{{0ex}{0ex}}Lu,{{0ex}{0ex}}Th,{{0ex}{0ex}}and{{0ex}{0ex}}U$. A thorough crystal-field analysis is presented for Pr${Be}₁₃$, Tm${Be}₁₃$, both ions being in a crystal-field singlet ground state, and the expected nuclear cooling and ordering behavior is also thoroughly discussed.