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Ba3CrN3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. Ba2+ is bonded in a 5-coordinate geometry to five equivalent N3- atoms. There are a spread of Ba–N bond distances ranging from 2.83–3.38 Å. Cr3+ is bonded in a trigonal planar geometry to three equivalent N3- atoms. All Cr–N bond lengths are 1.73 Å. N3- is bonded in a 1-coordinate geometry to five equivalent Ba2+ and one Cr3+ atom.
Ba5CrN5 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to four N3- atoms to form BaN4 trigonal pyramids that share corners with two equivalent CrN4 tetrahedra and an edgeedge with one BaN4 trigonal pyramid. There are a spread of Ba–N bond distances ranging from 2.64–2.85 Å. In the second Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven N3- atoms. There are a spread of Ba–N bond distances ranging from 2.82–3.08 Å. In the third Ba2+ site, Ba2+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Ba–N bond distances ranging from 2.72–2.93 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Ba–N bond distances ranging from 2.73–2.92 Å. Cr5+ is bonded to four N3- atoms to form CrN4 tetrahedra that share corners with two equivalent BaN4 trigonal pyramids. All Cr–N bond lengths are 1.76 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to six Ba2+ atoms to form edge-sharing NBa6 octahedra. In the second N3- site, N3- is bonded in a distorted single-bond geometry to five Ba2+ and one Cr5+ atom. In the third N3- site, N3- is bonded in a distorted single-bond geometry to five Ba2+ and one Cr5+ atom.
Ba(CrN2)2 crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve N3- atoms to form distorted BaN12 cuboctahedra that share corners with twelve equivalent CrN4 tetrahedra and edges with six equivalent CrN4 tetrahedra. There are six shorter (3.12 Å) and six longer (3.45 Å) Ba–N bond lengths. In the second Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine N3- atoms. There are a spread of Ba–N bond distances ranging from 2.88–3.09 Å. Cr5+ is bonded to four N3- atoms to form CrN4 tetrahedra that share corners with two equivalent BaN12 cuboctahedra, corners with four equivalent CrN4 tetrahedra, and an edgeedge with one BaN12 cuboctahedra. There are a spread of Cr–N bond distances ranging from 1.77–1.82 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted bent 120 degrees geometry to three Ba2+ and two equivalent Cr5+ atoms. In the second N3- site, N3- is bonded in a distorted bent 120 degrees geometry to two Ba2+ and two equivalent Cr5+ atoms.
Ba2CrN3 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven N3- atoms. There are a spread of Ba–N bond distances ranging from 2.88–3.15 Å. In the second Ba2+ site, Ba2+ is bonded to seven N3- atoms to form distorted BaN7 pentagonal bipyramids that share corners with four equivalent BaN7 pentagonal bipyramids, a cornercorner with one CrN4 tetrahedra, edges with three equivalent BaN7 pentagonal bipyramids, and edges with four equivalent CrN4 tetrahedra. There are a spread of Ba–N bond distances ranging from 2.83–2.95 Å. Cr5+ is bonded to four N3- atoms to form CrN4 tetrahedra that share a cornercorner with one BaN7 pentagonal bipyramid, corners with two equivalent CrN4 tetrahedra, and edges with four equivalent BaN7 pentagonal bipyramids. There are a spread of Cr–N bond distances ranging from 1.75–1.83 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded in a 2-coordinate geometry to four Ba2+ and two equivalent Cr5+ atoms. In the second N3- site, N3- is bonded in a distorted single-bond geometry to five Ba2+ and one Cr5+ atom. In the third N3- site, N3- is bonded in a distorted single-bond geometry to five Ba2+ and one Cr5+ atom.
BaCrN2 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. Ba2+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Ba–N bond distances ranging from 2.81–3.01 Å. Cr4+ is bonded to four N3- atoms to form a mixture of edge and corner-sharing CrN4 tetrahedra. There are a spread of Cr–N bond distances ranging from 1.79–1.87 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted bent 150 degrees geometry to two equivalent Ba2+ and two equivalent Cr4+ atoms. In the second N3- site, N3- is bonded in a 6-coordinate geometry to four equivalent Ba2+ and two equivalent Cr4+ atoms.