Materials Data on La3(CrN3)2 by Materials Project
La3Cr2N6 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to nine N3- atoms. There are a spread of La–N bond distances ranging from 2.55–2.74 Å. In the second La3+ site, La3+ is bonded in a body-centered cubic geometry to eight equivalent N3- atoms. All La–N bond lengths are 2.60 Å. Cr+4.50+ is bonded to five N3- atoms to form corner-sharing CrN5 square pyramids. There is one shorter (1.83 Å) and four longer (1.95 Å) Cr–N bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to five equivalent La3+ and one Cr+4.50+ atom to form distorted NLa5Cr octahedra that share corners with sixteen NLa5Cr octahedra, edges with eight equivalent NLa5Cr octahedra, and faces with four equivalent NLa4Cr2 octahedra. The corner-sharing octahedra tilt angles range from 12–54°. In the second N3- site, N3- is bonded to four La3+ and two equivalent Cr+4.50+ atoms to form distorted NLa4Cr2 octahedra that share corners with fourteen NLa5Cr octahedra, edges with three equivalent NLa4Cr2 octahedra, and faces with six NLa5Cr octahedra. The corner-sharing octahedra tilt angles range from 0–63°.