Materials Data on Tb2Fe17C2 by Materials Project

Tb2Fe17C2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Tb is bonded in a distorted bent 120 degrees geometry to nine Fe and two equivalent C atoms. There are a spread of Tb–Fe bond distances ranging from 3.05–3.37 Å. Both Tb–C bond lengths are 2.52 Å. There are seven inequivalent Fe sites. In the first Fe site, Fe is bonded in a 2-coordinate geometry to one Tb and thirteen Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.40–2.75 Å. In the second Fe site, Fe is bonded to three equivalent Tb and nine Fe atoms to form distorted FeTb3Fe9 cuboctahedra that share corners with nine FeTb3Fe9 cuboctahedra, corners with four equivalent CTb2Fe4 octahedra, edges with four FeTb3Fe9 cuboctahedra, faces with four FeTb3Fe9 cuboctahedra, and faces with two equivalent CTb2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 63–69°. There are a spread of Fe–Fe bond distances ranging from 2.47–2.64 Å. In the third Fe site, Fe is bonded in a single-bond geometry to five Fe and one C atom. There are a spread of Fe–Fe bond distances ranging from 2.47–2.57 Å. The Fe–C bond length is 1.91 Å. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Tb and ten Fe atoms. There are two shorter (2.44 Å) and two longer (2.48 Å) Fe–Fe bond lengths. In the fifth Fe site, Fe is bonded in a single-bond geometry to six Fe and one C atom. Both Fe–Fe bond lengths are 2.44 Å. The Fe–C bond length is 1.85 Å. In the sixth Fe site, Fe is bonded to two equivalent Tb and ten Fe atoms to form distorted FeTb2Fe10 cuboctahedra that share corners with ten FeTb3Fe9 cuboctahedra, edges with two equivalent FeTb3Fe9 cuboctahedra, faces with six FeTb3Fe9 cuboctahedra, and faces with four equivalent CTb2Fe4 octahedra. In the seventh Fe site, Fe is bonded to two equivalent Tb and ten Fe atoms to form FeTb2Fe10 cuboctahedra that share corners with six FeTb3Fe9 cuboctahedra, corners with two equivalent CTb2Fe4 octahedra, edges with two equivalent FeTb3Fe9 cuboctahedra, faces with six FeTb3Fe9 cuboctahedra, and faces with two equivalent CTb2Fe4 octahedra. The corner-sharing octahedral tilt angles are 45°. C is bonded to two equivalent Tb and four Fe atoms to form CTb2Fe4 octahedra that share corners with six FeTb3Fe9 cuboctahedra, corners with two equivalent CTb2Fe4 octahedra, and faces with six FeTb2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 63°.