Materials Data on ErNi2B2C by Materials Project
ErNi2B2C crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Er3+ is bonded in a square co-planar geometry to four equivalent C2- atoms. All Er–C bond lengths are 2.48 Å. Ni+2.50+ is bonded to four equivalent B3- atoms to form NiB4 tetrahedra that share corners with four equivalent CEr4B2 octahedra, corners with four equivalent NiB4 tetrahedra, and edges with four equivalent NiB4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. All Ni–B bond lengths are 2.08 Å. B3- is bonded in a distorted single-bond geometry to four equivalent Ni+2.50+ and one C2- atom. The B–C bond length is 1.49 Å. C2- is bonded to four equivalent Er3+ and two equivalent B3- atoms to form distorted CEr4B2 octahedra that share corners with four equivalent CEr4B2 octahedra, corners with eight equivalent NiB4 tetrahedra, and edges with four equivalent CEr4B2 octahedra. The corner-sharing octahedral tilt angles are 0°.