M 3 NS 3 (M = La – Nd, Sm, Gd – Dy): Struktur und Magnetismus von 3:1:3‐Typ‐Nitridsulfiden dreiwertiger Lanthanide

M 3 NS 3 (M = La – Nd, Sm, Gd – Dy): Structure and Magnetism of 3:1:3‐Type Nitride Sulfides of Trivalent Lanthanides Nitride sulfides of the trivalent lanthanides with the composition M 3 NS 3 (M = La – Nd, Sm, Gd – Dy) can be prepared by the oxidation of the respective lanthanide metal with sulfur, sodium azide (NaN 3 ), and the corresponding lanthanide tribromide (MBr 3 ) when an additional flux (NaBr) is used. Temperature ranges from 800 to 900 °C for the thermal treatment of the reaction mixtures in evacuated silica tubes secure the formation of bright to dark brown, transparent, lath shaped single‐crystals. The orthorhombic crystal structure ( Pnma , Z = 4) was determined from single‐crystal X‐ray diffraction data (La 3 NS 3 : a = 1215.13(5), b = 415.90(2), c = 1322.12(5) pm, Ce 3 NS 3 : a = 1206.28(4), b = 410.16(1), c = 1307.18(5) pm, Pr 3 NS 3 : a = 1205.45(7), b = 405.35(2), c = 1297.58(8) pm, Nd 3 NS 3 : a = 1207.82(5), b = 401.31(1), c = 1295.20(4) pm, Sm 3 NS 3 : a = 1201.58(6), b = 394.84(2), c = 1285.63(7) pm, Gd 3 NS 3 : a = 1197.17(7), b = 388.22(3), c = 1286.92(8) pm, Tb 3 NS 3 : a = 1191.62(7), b = 385.07(3), c = 1282.44(8) pm, and Dy 3 NS 3 : a = 1187.66(7), b = 382.55(3), c = 1276.77(8) pm). There are three crystallographically different M 3+ cations present in coordination of both the N 3− and the S 2− anions. However, [NM 4 ] 9+ tetrahedra connected via two common corners (c) to form linear chains $^{1}_{\infty}\rm \{[N(M1)^{t}_{1/1}(M2)^{t}_{1/1}(M3)^{c}_{2/2}]^{6+}\}$ along [010] build up the main structural feature. A non‐linear behaviour for the decreasing lattice constants of the pseudo ‐isotypic series from La 3 NS 3 to Dy 3 NS 3 concerning the a ‐ and c ‐axes is observed along with the lanthanoid contraction caused by the diminishing coordination sphere of (M1) 3+ (CN = 7) and (M3) 3+ (CN = 7) moving from the light to the heavier lanthanides. Curie‐Weiss ‐type magnetic behaviour for Dy 3 NS 3 with μ eff = 10.3(1) μ B for DyN 1/3 S corresponding to a 6 H 15/2 groundstate for Dy 3+ at higher temperatures and antiferromagnetic ordering of the Dy 3+ moments below 5 K is observed.