Materials Data on Sc2CrC3 by Materials Project

Abstract

Sc2CrC3 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are three inequivalent Sc3+ sites. In the first Sc3+ site, Sc3+ is bonded to seven C4- atoms to form ScC7 pentagonal bipyramids that share corners with three equivalent ScC6 octahedra, corners with four equivalent ScC7 pentagonal bipyramids, corners with six CSc5CrC pentagonal bipyramids, edges with three ScC6 octahedra, edges with two equivalent ScC7 pentagonal bipyramids, edges with six equivalent CrC5 trigonal bipyramids, and faces with two equivalent ScC7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 2–21°. There are a spread of Sc–C bond distances ranging from 2.21–2.47 Å. In the second Sc3+ site, Sc3+ is bonded to six C4- atoms to form ScC6 octahedra that share corners with two equivalent CSc4Cr2C pentagonal bipyramids, corners with six equivalent CrC5 trigonal bipyramids, edges with six ScC6 octahedra, edges with four equivalent ScC7 pentagonal bipyramids, and edges with two equivalent CrC5 trigonal bipyramids. There are four shorter (2.34 Å) and two longer (2.67 Å) Sc–C bond lengths. In the third Sc3+ site, Sc3+ is bonded to six C4- atoms to form ScC6 octahedra that share corners with four equivalent CSc4Cr2C pentagonal bipyramids, corners with six equivalent ScC7 pentagonal bipyramids, edges with six ScC6 octahedra, edges with two equivalent ScC7 pentagonal bipyramids, and edges with four equivalent CrC5 trigonal bipyramids. There are two shorter (2.26 Å) and four longer (2.47 Å) Sc–C bond lengths. Cr6+ is bonded to five C4- atoms to form distorted CrC5 trigonal bipyramids that share corners with three equivalent ScC6 octahedra, corners with three CSc5CrC pentagonal bipyramids, corners with four equivalent CrC5 trigonal bipyramids, edges with three ScC6 octahedra, and edges with six equivalent ScC7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 12–24°. There are a spread of Cr–C bond distances ranging from 1.97–2.09 Å. There are three inequivalent C4- sites. In the first C4- site, C4- is bonded to four Sc3+ and two equivalent Cr6+ atoms to form CSc4Cr2 octahedra that share corners with three equivalent CSc4Cr2 octahedra, corners with four equivalent CSc4Cr2C pentagonal bipyramids, edges with three equivalent CSc4Cr2 octahedra, and edges with eight CSc5CrC pentagonal bipyramids. The corner-sharing octahedral tilt angles are 0°. In the second C4- site, C4- is bonded to four equivalent Sc3+, two equivalent Cr6+, and one C4- atom to form distorted CSc4Cr2C pentagonal bipyramids that share corners with three ScC6 octahedra, corners with four equivalent CSc4Cr2 octahedra, corners with two equivalent ScC7 pentagonal bipyramids, corners with nine CSc4Cr2C pentagonal bipyramids, a cornercorner with one CrC5 trigonal bipyramid, edges with two equivalent CSc4Cr2 octahedra, edges with three CSc5CrC pentagonal bipyramids, and faces with three CSc5CrC pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 45–59°. The C–C bond length is 1.47 Å. In the third C4- site, C4- is bonded to five Sc3+, one Cr6+, and one C4- atom to form distorted CSc5CrC pentagonal bipyramids that share corners with four equivalent ScC7 pentagonal bipyramids, corners with eight CSc5CrC pentagonal bipyramids, corners with two equivalent CrC5 trigonal bipyramids, edges with six equivalent CSc4Cr2 octahedra, edges with four CSc5CrC pentagonal bipyramids, and a faceface with one CSc4Cr2C pentagonal bipyramid.