Materials Data on Na2ZnBr4 by Materials Project

Na2ZnBr4 is Spinel-like structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six Br1- atoms to form NaBr6 octahedra that share corners with four equivalent NaBr6 octahedra, corners with two equivalent ZnBr4 tetrahedra, edges with four NaBr6 octahedra, and edges with two equivalent ZnBr4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–60°. There are a spread of Na–Br bond distances ranging from 2.98–3.06 Å. In the second Na1+ site, Na1+ is bonded to six Br1- atoms to form NaBr6 octahedra that share corners with eight NaBr6 octahedra, corners with four equivalent ZnBr4 tetrahedra, edges with two equivalent NaBr6 octahedra, and an edgeedge with one ZnBr4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–60°. There are a spread of Na–Br bond distances ranging from 2.99–3.08 Å. Zn2+ is bonded to four Br1- atoms to form ZnBr4 tetrahedra that share corners with six NaBr6 octahedra and edges with three NaBr6 octahedra. The corner-sharing octahedra tilt angles range from 57–58°. There are a spread of Zn–Br bond distances ranging from 2.42–2.47 Å. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded to three Na1+ and one Zn2+ atom to form distorted corner-sharing BrNa3Zn trigonal pyramids. In the second Br1- site, Br1- is bonded in a rectangular see-saw-like geometry to three Na1+ and one Zn2+ atom. In the third Br1- site, Br1- is bonded in a rectangular see-saw-like geometry to three Na1+ and one Zn2+ atom.