Materials Data on K5Nb(CN)8 by Materials Project
NbK5(CN)8 crystallizes in the tetragonal I-4 space group. The structure is three-dimensional and consists of two columbium molecules and one K5(CN)8 framework. In the K5(CN)8 framework, there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.88–3.25 Å. In the second K1+ site, K1+ is bonded in a distorted square co-planar geometry to four equivalent N3- atoms. All K–N bond lengths are 2.86 Å. There are two inequivalent C+1.75+ sites. In the first C+1.75+ site, C+1.75+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.18 Å. In the second C+1.75+ site, C+1.75+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.19 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted single-bond geometry to four equivalent K1+ and one C+1.75+ atom. In the second N3- site, N3- is bonded in a distorted single-bond geometry to three K1+ and one C+1.75+ atom.