Synthesis and structure determination of Ce6Cd23Te: a new chalcogen‐containing member of the RE6Cd23T family (RE is a rare‐earth metal and T is a late group 14, 15 and 16 element)

The ternary phase hexacerium tricosacadmium telluride, Ce6Cd23Te, was synthesized by a high‐temperature reaction of the elements in sealed Nb ampoules and was structurally characterized by powder and single‐crystal X‐ray diffraction. The structure, established from single‐crystal X‐ray diffraction methods, is isopointal with the Zr6Zn23Si structure type (Pearson symbol cF120, cubic space group Fmm), a filled version of the Th6Mn23 structure with the same space group and Pearson symbol cF116. Though no Cd‐containing rare‐earth metal binaries are known to form with this structure, it appears that the addition of small amounts of a p‐block element allows the formation of such interstitially stabilized ternary compounds. Temperature‐dependent direct current (dc) magnetization measurements suggest local‐moment magnetism arising from the Ce3+ ground state, with possible valence fluctuations at low temperature, inferred from the deviations from the Curie–Weiss law. Ce6Cd23Te is a new intermetallic phase belonging to the extended RE6Cd23T family, up until now known to encompass RE = La–Nd, Sm, and Gd, and T = Sn, Pb, Sb, and Bi. It is the first known compound in the Ce–Cd–Te ternary phase diagram.