| Summary: | The three compounds Tl<sub>9</sub><i>RE</i>Te<sub>6</sub> with <i>RE</i> = Ce, Sm, Gd were synthesized from the elements at 1020 K. Their isostructural crystal structures are ordered derivatives of the Tl<sub>5</sub>Te<sub>3</sub> type with rare-earth metal and thallium occupying different Wyckoff positions. The structures can be understood as charge-ordered in accordance with the Zintl-Klemm concept: 9 Tl<sup>+</sup> + <i>RE</i><sup>3+</sup> + 6 Te<sup>2−</sup>. DFT calculations for Tl<sub>9</sub>GdTe<sub>6</sub>, however, result in a low, but finite density of states at the Fermi level. Magnetic data confirm trivalent Gd, but indicate a small amount of Ce<sup>4+</sup> in Tl<sub>9</sub>CeTe<sub>6</sub>; no indications for long-range magnetic order was found down to <i>T</i> = 2 K.
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