DOI: 10.17188/1275286
title: Materials Data on Zr3(Al2C3)2 by Materials Project

description: Zr3Al4C6 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing ZrC6 octahedra. The corner-sharing octahedral tilt angles are 1°. All Zr–C bond lengths are 2.38 Å. In the second Zr4+ site, Zr4+ is bonded to six C4- atoms to form ZrC6 octahedra that share corners with three equivalent ZrC6 octahedra, corners with three equivalent AlC4 tetrahedra, edges with nine ZrC6 octahedra, and edges with three equivalent AlC4 tetrahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (2.35 Å) and three longer (2.40 Å) Zr–C bond lengths. In the third Zr4+ site, Zr4+ is bonded to six C4- atoms to form ZrC6 octahedra that share corners with three equivalent ZrC6 octahedra, corners with three equivalent AlC4 tetrahedra, edges with nine ZrC6 octahedra, and edges with three equivalent AlC4 tetrahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (2.35 Å) and three longer (2.40 Å) Zr–C bond lengths. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four C4- atoms to form a mixture of corner and edge-sharing AlC4 trigonal pyramids. There are three shorter (1.96 Å) and one longer (2.18 Å) Al–C bond lengths. In the second Al3+ site, Al3+ is bonded to four C4- atoms to form AlC4 tetrahedra that share corners with three equivalent ZrC6 octahedra, corners with six equivalent AlC4 tetrahedra, corners with four AlC4 trigonal pyramids, and edges with three equivalent ZrC6 octahedra. The corner-sharing octahedral tilt angles are 12°. There are one shorter (1.95 Å) and three longer (2.13 Å) Al–C bond lengths. In the third Al3+ site, Al3+ is bonded to four C4- atoms to form AlC4 tetrahedra that share corners with three equivalent ZrC6 octahedra, corners with six equivalent AlC4 tetrahedra, corners with four AlC4 trigonal pyramids, and edges with three equivalent ZrC6 octahedra. The corner-sharing octahedral tilt angles are 12°. There are one shorter (1.95 Å) and three longer (2.13 Å) Al–C bond lengths. In the fourth Al3+ site, Al3+ is bonded to four C4- atoms to form a mixture of corner and edge-sharing AlC4 trigonal pyramids. There are three shorter (1.96 Å) and one longer (2.18 Å) Al–C bond lengths. There are six inequivalent C4- sites. In the first C4- site, C4- is bonded to five Al3+ atoms to form CAl5 trigonal bipyramids that share corners with three equivalent CZr3Al3 octahedra, corners with six equivalent CAl5 trigonal bipyramids, and edges with three equivalent CAl5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 65°. In the second C4- site, C4- is bonded to three equivalent Zr4+ and three equivalent Al3+ atoms to form CZr3Al3 octahedra that share corners with three equivalent CZr6 octahedra, corners with three equivalent CAl5 trigonal bipyramids, and edges with nine CZr6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the third C4- site, C4- is bonded to five Al3+ atoms to form CAl5 trigonal bipyramids that share corners with three equivalent CZr3Al3 octahedra, corners with six equivalent CAl5 trigonal bipyramids, and edges with three equivalent CAl5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 66°. In the fourth C4- site, C4- is bonded to six Zr4+ atoms to form a mixture of corner and edge-sharing CZr6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fifth C4- site, C4- is bonded to three equivalent Zr4+ and three equivalent Al3+ atoms to form CZr3Al3 octahedra that share corners with three equivalent CZr6 octahedra, corners with three equivalent CAl5 trigonal bipyramids, and edges with nine CZr3Al3 octahedra. The corner-sharing octahedral tilt angles are 2°. In the sixth C4- site, C4- is bonded to six Zr4+ atoms to form a mixture of corner and edge-sharing CZr6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°.