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Cr3N2 crystallizes in the trigonal P321 space group. The structure is two-dimensional and consists of one Cr3N2 sheet oriented in the (0, 0, 1) direction. Cr2+ is bonded in a bent 120 degrees geometry to two equivalent N3- atoms. Both Cr–N bond lengths are 1.82 Å. N3- is bonded in a distorted T-shaped geometry to three equivalent Cr2+ atoms.
Cr3N2 crystallizes in the monoclinic C2 space group. The structure is two-dimensional and consists of one Cr3N2 sheet oriented in the (0, 0, 1) direction. there are two inequivalent Cr2+ sites. In the first Cr2+ site, Cr2+ is bonded in a bent 120 degrees geometry to two equivalent N3- atoms. Both Cr–N bond lengths are 1.80 Å. In the second Cr2+ site, Cr2+ is bonded in a bent 120 degrees geometry to two equivalent N3- atoms. Both Cr–N bond lengths are 1.80 Å. N3- is bonded in a trigonal planar geometry to three Cr2+ atoms.
Cr3N2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Cr2+ sites. In the first Cr2+ site, Cr2+ is bonded in a linear geometry to two equivalent N3- atoms. Both Cr–N bond lengths are 1.94 Å. In the second Cr2+ site, Cr2+ is bonded to five equivalent N3- atoms to form a mixture of corner and edge-sharing CrN5 square pyramids. There are four shorter (2.03 Å) and one longer (2.06 Å) Cr–N bond lengths. N3- is bonded to six Cr2+ atoms to form a mixture of corner and edge-sharing NCr6 octahedra. The corner-sharing octahedra tilt angles range from 0–10°.
Cr3N2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Cr2+ sites. In the first Cr2+ site, Cr2+ is bonded to four equivalent N3- atoms to form distorted CrN4 tetrahedra that share corners with six equivalent CrN6 octahedra, corners with six equivalent CrN4 tetrahedra, edges with three equivalent CrN6 octahedra, and edges with three equivalent CrN4 tetrahedra. The corner-sharing octahedra tilt angles range from 24–51°. There are three shorter (1.87 Å) and one longer (2.34 Å) Cr–N bond lengths. In the second Cr2+ site, Cr2+ is bonded to six equivalent N3- atoms to form CrN6 octahedra that share corners with twelve equivalent CrN4 tetrahedra, edges with six equivalent CrN6 octahedra, and edges with six equivalent CrN4 tetrahedra. There are two shorter (2.30 Å) and four longer (2.35 Å) Cr–N bond lengths. N3- is bonded in a 3-coordinate geometry to seven Cr2+ atoms.
Cr3N2 is Corundum-like structured and crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. there are two inequivalent Cr2+ sites. In the first Cr2+ site, Cr2+ is bonded to four equivalent N3- atoms to form a mixture of distorted corner and edge-sharing CrN4 trigonal pyramids. There are a spread of Cr–N bond distances ranging from 1.94–2.14 Å. In the second Cr2+ site, Cr2+ is bonded to four equivalent N3- atoms to form a mixture of distorted corner and edge-sharing CrN4 trigonal pyramids. There is two shorter (1.94 Å) and two longer (2.02 Å) Cr–N bond length. N3- is bonded to six Cr2+ atoms to form a mixture of corner, edge, and face-sharing NCr6 octahedra. The corner-sharing octahedra tilt angles range from 49–71°.