Preparation and X-ray diffraction study of PaBe13, AmBe13, and CmBe13

PaBe13, AmBe13 and CmBe13 were prepared by beryllothermic reduction of the corresponding oxides. Start and completion of the reaction were monitored by a neutron rem-counter. The compounds are of NaZn13 structure-type with a = 10.26 (PaBe13), a = 10.29 (AmBe13), and a = 10.27 (CmBe13). Increase of the lattice parameter of CmBe13 by self-irradiation damage is much slower than with curium oxides. The lattice parameters of beryllium-rich and actinide-rich AnBe13 compounds are compared with the lattice parameter curve of 1 : 13 lanthanide beryllides. A review of the distribution of known NaZn13-type compounds throughout the Periodic Table and on their relative X-ray diffraction line intensities has been made. (Auth.)