Materials Data on Zr2Al3C4 by Materials Project

Abstract

Zr2Al3C4 crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Zr2Al2C3 sheet oriented in the (0, 0, 1) direction and one Zr2Al4C5 sheet oriented in the (0, 0, 1) direction. In the Zr2Al2C3 sheet, Zr+3.50+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing ZrC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.31 Å) and three longer (2.53 Å) Zr–C bond lengths. Al3+ is bonded in a trigonal non-coplanar geometry to three equivalent C4- atoms. All Al–C bond lengths are 2.01 Å. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six equivalent Zr+3.50+ atoms to form edge-sharing CZr6 octahedra. In the second C4- site, C4- is bonded in a 6-coordinate geometry to three equivalent Zr+3.50+ and three equivalent Al3+ atoms. In the Zr2Al4C5 sheet, Zr+3.50+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing ZrC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.34 Å) and three longer (2.39 Å) Zr–C bond lengths. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded in a trigonal planar geometry to three equivalent C4- atoms. All Al–C bond lengths are 1.95 Å. In the second Al3+ site, Al3+ is bonded in a 3-coordinate geometry to six C4- atoms. There are three shorter (2.11 Å) and three longer (2.58 Å) Al–C bond lengths. There are three inequivalent C4- sites. In the first C4- site, C4- is bonded to six equivalent Zr+3.50+ atoms to form CZr6 octahedra that share corners with six equivalent CZr3Al3 octahedra and edges with twelve CZr6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the second C4- site, C4- is bonded to three equivalent Zr+3.50+ and three equivalent Al3+ atoms to form a mixture of corner and edge-sharing CZr3Al3 octahedra. The corner-sharing octahedral tilt angles are 2°. In the third C4- site, C4- is bonded in a distorted trigonal planar geometry to six Al3+ atoms.