Renaissance of the Stella Quadrangula: The Lanthanoid Nitride Tellurides LnLn ₁₃13 N ₅5 Te ₁₂12 ( LnLn = La–Nd)

摘要

> Ln ₁₃ N ₅ Te ₁₂ ( Ln = La–Nd), a quite unusual composition of the lanthanoid(III) nitride tellurides, appears with a new crystal structure and can be obtained by reactions of lanthanoid metal ( Ln ) with elemental tellurium (Te), sodium azide (NaN ₃ ), elemental iodine (I ₂ ) and sodium iodide (NaI) as flux in evacuated fused silica tubes for seven days at 900 °C. The black, shard‐shaped single crystals of the short new series Ln ₁₃ N ₅ Te ₁₂ ( Ln = La–Nd) crystallize monoclinically in the space group P 2 ₁ / m with lattice parameters ranging from a = 1039.86(7), b = 1373.29(9), c = 1311.78(9) pm, β = 100.103(3)° for La ₁₃ N ₅ Te ₁₂ to a = 1016.73(7), b = 1337.58(9), c = 1288.92(9) pm, β = 100.094(3)° for Nd ₁₃ N ₅ Te ₁₂ and Z = 2. Unlike the other ternary compounds of the lanthanoid(III) nitride tellurides, two different types of isolated oligomers containing edge‐sharing [N Ln ₄ ] 9+ tetrahedra occur in their crystal structure. The fusion of two [N Ln ₄ ] 9+ units via one co