Materials Data on ScNiC2 by Materials Project
ScNiC2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Sc3+ is bonded to five equivalent C+2.50- atoms to form a mixture of distorted edge and corner-sharing ScC5 square pyramids. There are one shorter (2.20 Å) and four longer (2.39 Å) Sc–C bond lengths. Ni2+ is bonded to four equivalent C+2.50- atoms to form NiC4 tetrahedra that share corners with four equivalent CSc5C octahedra, corners with four equivalent NiC4 tetrahedra, and edges with four equivalent NiC4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. All Ni–C bond lengths are 2.06 Å. There are two inequivalent C+2.50- sites. In the first C+2.50- site, C+2.50- is bonded in a 5-coordinate geometry to four equivalent Ni2+ and one C+2.50- atom. The C–C bond length is 1.37 Å. In the second C+2.50- site, C+2.50- is bonded to five equivalent Sc3+ and one C+2.50- atom to form CSc5C octahedra that share corners with four equivalent CSc5C octahedra, corners with four equivalent NiC4 tetrahedra, and edges with eight equivalent CSc5C octahedra. The corner-sharing octahedral tilt angles are 4°.