Cs2Gd6N2Te7: The first quaternary nitride telluride of the lanthanides

A Nitrido‐Centered Uranium Azido Cluster Obtained from a Uranium Azide

“…[15] N 3À -centered tetrahedra are found in the crystal structures of quaternary nitride tellurides of lanthanides prepared by a high-temperature, solid-state reaction; [27] the reported anisotropic thermal parameters are very similar to those found in the structure refinement of 3. The UV/Vis/NIR spectrum of 3 shows absorption maxima only at 694 and 1153 nm, which is typical for U IV species.…”

Förderung der Grundlagenforschung

“…In analogy to the lattice parameters of this short series all distances (Table 4) between the Ln 3+ cations ( Ln = Gd–Ho) and their ligands (N 3– and Te 2– ) comply with the lanthanoid‐contractive behavior. The Ln 3+ –Te 2– distances can be compared quite well with the primary contacts (306–348 pm) of the ternary Ln 4 N 2 Te 3 examples ( Ln = Tb and Dy)25 on the one hand and with the distances (305–327 pm) of the quaternary compounds Cs 2 Ln 6 N 2 Te 7 ( Ln = Gd and Tb)26,27 on the other hand. The higher values of the first‐mentioned nitride‐rich representatives Ln 4 N 2 Te 3 ( Ln = Tb and Dy) can be explained well with the higher coordination numbers (CN = 7) and the correlated distortion grades of the coordination figures.…”

“…But not only the symmetry changes, since infinite chains 1 ∞ {[N Ln t 2/1 Ln ′ v 2/2 ] 6+ } (t = terminal, v = vertex‐connecting), of vertex‐sharing [N Ln 4 ] 9+ tetrahedra as main structural feature for almost all Ln 3 N Ch 3 ( Ln = La–Nd, Sm, Gd–Ho; Ch = S, Se)5,13–16 examples cannot be realized any more in the crystal structure of Ho 3 NSe 3 13 (Figure 4). The latter resembles a lot the crystallographic arrangement of the new lanthanoid(III) nitride tellurides Ln 3 NTe 3 ( Ln = Gd–Ho), whereas the first ones appear again in the quaternary nitride‐telluride examples Cs 2 Ln 6 N 2 Te 7 ( Ln = Gd and Tb) 26,27. Many nitride‐based lanthanoid compounds have anti ‐isotypic relationships to cation‐rich oxides or Zintl phases.…”

“…Chains of vertex‐connected [N Ln 4 ] 9+ tetrahedra dominate the crystal structures of nitride sulfides and selenides for the Ln 3 N Ch 3 series ( Ln = La–Nd, Sm, Gd–Dy; Ch = S and Se)5,13–16 according to 1 ∞ {[N Ln t 2/1 Ln ′ v 2/2 ] 6+ } (t = terminal, v = vertex‐connecting) with two shared corners per [N Ln 4 ] 9+ unit. Nitride tellurides, however, seem to need another derivatizing cation such as Cs + in order to achieve the same in the quaternary examples Cs 2 Ln 6 N 2 Te 7 26,27. The alternative to infinite chains 1 ∞ {[N Ln t 2/1 Ln ′ v 2/2 ] 6+ } with vertex‐connectivity are so far unknown isolated n‐membered rings 0 ∞ {[N Ln t 2/1 Ln ′ v 2/2 ]} n ) 6 n + } with vertex‐connectivity for n ≥ 3 or dimers 0 ∞ {[N Ln t 2/1 Ln ′ e 2/2 ] n ) 6 n + } (≡ [N 2 Ln 6 ] 12+ ) with edge‐connectivity for n = 2 as long as fused [N Ln 4 ] 9+ tetrahedra persist.…”

Lanthanido ammonium cations [NM4]9+ as main structural features in lanthanide(III) nitride chalcogenides and their derivatives

“…With the stoichiometry N:Sm = 1:3 it is possible to form discrete [N 2 Sm 6 ] 12+ units like in Pr 5 NSe 6 [19], but this time a one-dimensional infinite chain solution is preferred. The [NSm 4 ] 9+ tetrahedra thus are connected via two common corners (Sm3) to form linear chains 1 [21]. Three crystallographically different Gd 3+ cations constitute the structure, but all are coordinated by distorted anionic octahedra.…”