Materials Data on Zr3AlN4 by Materials Project

Abstract

Zr3AlN4 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Zr3+ sites. In the first Zr3+ site, Zr3+ is bonded to six N3- atoms to form ZrN6 octahedra that share corners with six equivalent ZrN6 octahedra, edges with four equivalent AlN6 octahedra, and edges with eight ZrN6 octahedra. The corner-sharing octahedra tilt angles range from 0–11°. There are a spread of Zr–N bond distances ranging from 2.23–2.28 Å. In the second Zr3+ site, Zr3+ is bonded to six N3- atoms to form ZrN6 octahedra that share corners with two equivalent AlN6 octahedra, corners with four equivalent ZrN6 octahedra, and edges with twelve ZrN6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.27 Å) and two longer (2.47 Å) Zr–N bond lengths. Al3+ is bonded to six N3- atoms to form AlN6 octahedra that share corners with two equivalent ZrN6 octahedra, corners with four equivalent AlN6 octahedra, edges with four equivalent AlN6 octahedra, and edges with eight equivalent ZrN6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.02 Å) and four longer (2.27 Å) Al–N bond lengths. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to five Zr3+ and one Al3+ atom to form a mixture of corner and edge-sharing NZr5Al octahedra. The corner-sharing octahedra tilt angles range from 0–11°. In the second N3- site, N3- is bonded to two equivalent Zr3+ and four equivalent Al3+ atoms to form NZr2Al4 octahedra that share corners with six NZr2Al4 octahedra and edges with twelve NZr5Al octahedra. The corner-sharing octahedral tilt angles are 0°. In the third N3- site, N3- is bonded to six Zr3+ atoms to form NZr6 octahedra that share corners with six NZr2Al4 octahedra and edges with twelve NZr5Al octahedra. The corner-sharing octahedral tilt angles are 0°.