Preparation and crystal structure of the ternary uranium rare Earth antimonides (U(2/3)R(1/3))Sb(2) and (U(1/2)R(1/2))(3)Sb(7) with mixed U/R occupancy of the metal sites and a variety of antimony polyanions

Yet again, new compounds found in systems with known binary phase diagrams. Synthesis, crystal and electronic structure of Nd3Bi7 and Sm3Bi7

The binary bismuthides Nd3Bi7 and Sm3Bi7 were synthesized and structurally characterized for the first time. The results from the calorimetric analysis show that both compounds are stable only up to about 500 °C, which may explain why they were overlooked during the original assessment of the corresponding phase diagrams.

The single crystal structure determination of Ln6MnSb15 (Ln=La, Ce), Ln6Mn1−xZnxSb15 (x~0.5), and Ln6ZnSb15 (Ln=La–Pr)

Single crystals of Ln6MnSb15 (Ln=La, Ce), Ln6Mn1−xZnxSb15 (x~0.5), and Ln6ZnSb15 (Ln=La–Pr) have been successfully grown and the compounds adopt the orthorhombic La6MnSb15 structure type (space group Immm), with a~4.3 Å, b~15 Å, and c~19 Å. This structure is comprised of antimony nets and antimony ribbons which exhibit positional disorder at connecting points between antimony substructures, in addition to two partially occupied transition metal sites. The unit cell volumes of the La analogs displayed a systematic decrease upon Zn substitution. However, for the Ce6Mn1−xZnxSb15 and Pr6Mn1−xZnxSb15 (x~0.5), the volumes deviate from linearity as observed in the parent compounds.