Materials Data on Zr3Sc4N8 by Materials Project

Abstract

Sc4Zr3N8 crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of three Sc4Zr3N8 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Sc3+ sites. In the first Sc3+ site, Sc3+ is bonded in a 6-coordinate geometry to six N3- atoms. There are three shorter (2.04 Å) and three longer (2.55 Å) Sc–N bond lengths. In the second Sc3+ site, Sc3+ is bonded to six N3- atoms to form ScN6 octahedra that share corners with three equivalent ZrN6 octahedra, edges with three equivalent ZrN6 octahedra, and edges with six equivalent ScN6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are three shorter (2.13 Å) and three longer (2.48 Å) Sc–N bond lengths. There are two inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded to six N3- atoms to form ZrN6 octahedra that share corners with three equivalent ScN6 octahedra, corners with three equivalent ZrN6 octahedra, edges with three equivalent ScN6 octahedra, and edges with nine ZrN6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are three shorter (2.23 Å) and three longer (2.33 Å) Zr–N bond lengths. In the second Zr4+ site, Zr4+ is bonded to six equivalent N3- atoms to form a mixture of corner and edge-sharing ZrN6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Zr–N bond lengths are 2.33 Å. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal non-coplanar geometry to three equivalent Sc3+ atoms. In the second N3- site, N3- is bonded to six Sc3+ atoms to form distorted NSc6 octahedra that share corners with three equivalent NZr3Sc3 octahedra and edges with nine NSc6 octahedra. The corner-sharing octahedral tilt angles are 13°. In the third N3- site, N3- is bonded to three equivalent Sc3+ and three equivalent Zr4+ atoms to form a mixture of corner and edge-sharing NZr3Sc3 octahedra. The corner-sharing octahedra tilt angles range from 4–13°. In the fourth N3- site, N3- is bonded to six Zr4+ atoms to form a mixture of corner and edge-sharing NZr6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°.