Materials Data on Na3BrCl2 by Materials Project
Na3BrCl2 is Caswellsilverite-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to one Br1- and five equivalent Cl1- atoms to form a mixture of edge and corner-sharing NaBrCl5 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. The Na–Br bond length is 2.97 Å. There are one shorter (2.84 Å) and four longer (2.92 Å) Na–Cl bond lengths. In the second Na1+ site, Na1+ is bonded to four equivalent Br1- and two equivalent Cl1- atoms to form a mixture of edge and corner-sharing NaBr4Cl2 octahedra. The corner-sharing octahedral tilt angles are 0°. All Na–Br bond lengths are 2.92 Å. Both Na–Cl bond lengths are 2.93 Å. In the third Na1+ site, Na1+ is bonded to four equivalent Br1- and two equivalent Cl1- atoms to form a mixture of edge and corner-sharing NaBr4Cl2 octahedra. The corner-sharing octahedral tilt angles are 0°. All Na–Br bond lengths are 2.92 Å. Both Na–Cl bond lengths are 2.93 Å. Br1- is bonded to six Na1+ atoms to form BrNa6 octahedra that share corners with two equivalent ClNa6 octahedra, corners with four equivalent BrNa6 octahedra, edges with four equivalent BrNa6 octahedra, and edges with eight equivalent ClNa6 octahedra. The corner-sharing octahedral tilt angles are 0°. Cl1- is bonded to six Na1+ atoms to form ClNa6 octahedra that share a cornercorner with one BrNa6 octahedra, corners with five equivalent ClNa6 octahedra, edges with four equivalent BrNa6 octahedra, and edges with eight equivalent ClNa6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°.