DOI: 10.17188/1739371
title: Materials Data on Sc4BC4 by Materials Project

description: Sc4BC4 crystallizes in the tetragonal P4/mmm space group. The structure is two-dimensional and consists of one Sc4BC4 sheet oriented in the (0, 0, 1) direction. there are six inequivalent Sc3+ sites. In the first Sc3+ site, Sc3+ is bonded to six C+3.75- atoms to form ScC6 octahedra that share corners with four equivalent ScC6 octahedra, edges with four equivalent ScC6 octahedra, and edges with eight ScC5 square pyramids. The corner-sharing octahedral tilt angles are 2°. There are a spread of Sc–C bond distances ranging from 2.35–2.45 Å. In the second Sc3+ site, Sc3+ is bonded to six C+3.75- atoms to form ScC6 octahedra that share corners with four equivalent ScC6 octahedra, edges with four equivalent ScC6 octahedra, and edges with eight ScC5 square pyramids. The corner-sharing octahedral tilt angles are 0°. There are a spread of Sc–C bond distances ranging from 2.35–2.42 Å. In the third Sc3+ site, Sc3+ is bonded to five C+3.75- atoms to form ScC5 square pyramids that share corners with five ScC5 square pyramids, edges with four equivalent ScC6 octahedra, and edges with four equivalent ScC5 square pyramids. There are one shorter (2.30 Å) and four longer (2.36 Å) Sc–C bond lengths. In the fourth Sc3+ site, Sc3+ is bonded to five C+3.75- atoms to form ScC5 square pyramids that share corners with five ScC5 square pyramids, edges with four equivalent ScC6 octahedra, and edges with four equivalent ScC5 square pyramids. There are one shorter (2.19 Å) and four longer (2.36 Å) Sc–C bond lengths. In the fifth Sc3+ site, Sc3+ is bonded to five C+3.75- atoms to form ScC5 square pyramids that share corners with five ScC5 square pyramids, edges with four equivalent ScC6 octahedra, and edges with four equivalent ScC5 square pyramids. There are one shorter (2.19 Å) and four longer (2.36 Å) Sc–C bond lengths. In the sixth Sc3+ site, Sc3+ is bonded to five C+3.75- atoms to form ScC5 square pyramids that share corners with five ScC5 square pyramids, edges with four equivalent ScC6 octahedra, and edges with four equivalent ScC5 square pyramids. There are one shorter (2.17 Å) and four longer (2.36 Å) Sc–C bond lengths. There are two inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a linear geometry to two C+3.75- atoms. There is one shorter (1.45 Å) and one longer (1.47 Å) B–C bond length. In the second B3+ site, B3+ is bonded in a linear geometry to two equivalent C+3.75- atoms. Both B–C bond lengths are 1.46 Å. There are six inequivalent C+3.75- sites. In the first C+3.75- site, C+3.75- is bonded to six Sc3+ atoms to form CSc6 octahedra that share corners with four equivalent CSc6 octahedra, edges with eight CSc5B octahedra, and edges with four equivalent CSc5 square pyramids. The corner-sharing octahedral tilt angles are 2°. In the second C+3.75- site, C+3.75- is bonded to six Sc3+ atoms to form a mixture of edge and corner-sharing CSc6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third C+3.75- site, C+3.75- is bonded to five Sc3+ atoms to form CSc5 square pyramids that share a cornercorner with one CSc5B octahedra, corners with four equivalent CSc5 square pyramids, edges with four equivalent CSc6 octahedra, and edges with four equivalent CSc5 square pyramids. The corner-sharing octahedral tilt angles are 0°. In the fourth C+3.75- site, C+3.75- is bonded to five Sc3+ and one B3+ atom to form distorted CSc5B octahedra that share corners with six CSc5B octahedra and edges with eight CSc6 octahedra. The corner-sharing octahedra tilt angles range from 0–11°. In the fifth C+3.75- site, C+3.75- is bonded to five Sc3+ and one B3+ atom to form distorted CSc5B octahedra that share corners with six CSc5B octahedra and edges with eight CSc6 octahedra. The corner-sharing octahedra tilt angles range from 0–11°. In the sixth C+3.75- site, C+3.75- is bonded to five Sc3+ and one B3+ atom to form distorted CSc5B octahedra that share corners with five CSc5B octahedra, a cornercorner with one CSc5 square pyramid, and edges with eight CSc5B octahedra. The corner-sharing octahedra tilt angles range from 0–12°.