Materials Data on Ho3C4 by Materials Project

Abstract

Ho3C4 crystallizes in the tetragonal P4/mnc space group. The structure is three-dimensional. there are four inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to six C+2.25- atoms to form HoC6 octahedra that share corners with two equivalent HoC6 octahedra, corners with four equivalent HoC7 pentagonal bipyramids, and edges with four equivalent HoC7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.49 Å) and four longer (2.60 Å) Ho–C bond lengths. In the second Ho3+ site, Ho3+ is bonded to six C+2.25- atoms to form HoC6 octahedra that share a cornercorner with one HoC6 octahedra and edges with four equivalent HoC7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 0°. There are a spread of Ho–C bond distances ranging from 2.33–2.62 Å. In the third Ho3+ site, Ho3+ is bonded to seven C+2.25- atoms to form distorted HoC7 pentagonal bipyramids that share a cornercorner with one HoC6 octahedra, corners with two equivalent HoC7 pentagonal bipyramids, edges with three HoC6 octahedra, edges with two equivalent HoC7 pentagonal bipyramids, and faces with two equivalent HoC7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 1°. There are a spread of Ho–C bond distances ranging from 2.48–2.74 Å. In the fourth Ho3+ site, Ho3+ is bonded in a 7-coordinate geometry to seven C+2.25- atoms. There are a spread of Ho–C bond distances ranging from 2.34–2.83 Å. There are seven inequivalent C+2.25- sites. In the first C+2.25- site, C+2.25- is bonded to six Ho3+ atoms to form a mixture of edge and corner-sharing CHo6 octahedra. The corner-sharing octahedra tilt angles range from 0–85°. In the second C+2.25- site, C+2.25- is bonded to six Ho3+ atoms to form a mixture of edge and corner-sharing CHo6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. Both C–Ho bond lengths are 2.34 Å. In the third C+2.25- site, C+2.25- is bonded to six Ho3+ atoms to form a mixture of edge and corner-sharing CHo6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. Both C–Ho bond lengths are 2.34 Å. In the fourth C+2.25- site, C+2.25- is bonded to six Ho3+ atoms to form a mixture of edge and corner-sharing CHo6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the fifth C+2.25- site, C+2.25- is bonded to five Ho3+ and one C+2.25- atom to form a mixture of edge and corner-sharing CHo5C octahedra. The corner-sharing octahedra tilt angles range from 4–85°. The C–C bond length is 1.35 Å. In the sixth C+2.25- site, C+2.25- is bonded in a 2-coordinate geometry to four equivalent Ho3+ and two equivalent C+2.25- atoms. In the seventh C+2.25- site, C+2.25- is bonded in a 6-coordinate geometry to five Ho3+ and one C+2.25- atom. The C–C bond length is 1.31 Å.