Department of Chemistry2024-11-0920070932-077610.1515/znb-2007-10032-s2.0-35248857476http://dx.doi.org/10.1515/znb-2007-1003https://hdl.handle.net/20.500.14288/12864Coppery-red, transparent single crystals of (Ba6N 5/6)2[NbN4][CN2]6 [NbN4] [CN2]6 (Im3̄, no. 204, a = 1125.83(3) pm, Z = 2) are obtained by the reaction of Ba2N and ZnCN2 with the container walls of the arc-welded Nb ampoules at 1100 K. The title compound assumes a stuffed skutterudite-type structure in which edge-sharing (Ba6N5/6) octahedra form large voids which are occupied by either [NbN4] tetrahedra or by [N=C=N]2- units with symmetric C=N bond lengths of d = 121.8(6) pm but a bond angle deviating significantly from linearity (∠(N-C-N) = 175.3(9)°). The IR spectra corroborate this crystallographic result by the fact that all fundamental vibrations are visible in the IR spectrum [v1 = 1262 (symmetric stretching mode); v2 = 1957/2009 (antisymmetric stretching mode); v3 = 611/633/653 cm-1 (bending modes)], which is symmetry forbidden for [N=C=N]2- units having D∞h symmetry but expected for the C2v symmetry found in the title compound.ChemistryJournal Article1865-7117https://www.scopus.com/inward/record.uri?eid=2-s2.0-35248857476anddoi=10.1515%2fznb-2007-1003andpartnerID=40andmd5=c6d8ae723d3ae6806fff5f3a072188abQ47860