Materials Data on Na5Br4Cl by Materials Project

Abstract

Na5Br4Cl is Caswellsilverite-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six Br1- atoms to form a mixture of edge and corner-sharing NaBr6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Na–Br bond lengths are 2.99 Å. In the second Na1+ site, Na1+ is bonded to five Br1- and one Cl1- atom to form a mixture of edge and corner-sharing NaBr5Cl octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are four shorter (2.99 Å) and one longer (3.01 Å) Na–Br bond lengths. The Na–Cl bond length is 2.96 Å. In the third Na1+ site, Na1+ is bonded to two equivalent Br1- and four equivalent Cl1- atoms to form NaBr2Cl4 octahedra that share corners with six NaBr6 octahedra and edges with twelve NaBr5Cl octahedra. The corner-sharing octahedral tilt angles are 0°. Both Na–Br bond lengths are 2.98 Å. All Na–Cl bond lengths are 2.99 Å. In the fourth Na1+ site, Na1+ is bonded to six Br1- atoms to form a mixture of edge and corner-sharing NaBr6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Na–Br bond lengths are 2.99 Å. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded to six Na1+ atoms to form BrNa6 octahedra that share corners with six BrNa6 octahedra, edges with four equivalent ClNa6 octahedra, and edges with eight BrNa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second Br1- site, Br1- is bonded to six Na1+ atoms to form BrNa6 octahedra that share a cornercorner with one ClNa6 octahedra, corners with five BrNa6 octahedra, and edges with twelve BrNa6 octahedra. The corner-sharing octahedral tilt angles are 0°. Cl1- is bonded to six Na1+ atoms to form ClNa6 octahedra that share corners with two equivalent BrNa6 octahedra, corners with four equivalent ClNa6 octahedra, edges with four equivalent ClNa6 octahedra, and edges with eight equivalent BrNa6 octahedra. The corner-sharing octahedral tilt angles are 0°.