K3BrCl2 is Caswellsilverite-like structured and crystallizes in the trigonal P-3m1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to six equivalent Cl(1) atoms to form KCl6 octahedra that share corners with six equivalent K(2)Br3Cl3 octahedra, edges with six equivalent K(2)Br3Cl3 octahedra, and edges with six equivalent K(1)Cl6 octahedra. The corner-sharing octahedra are not tilted. In the second K site, K(2) is bonded to three equivalent Br(1) and three equivalent Cl(1) atoms to form KBr3Cl3 octahedra that share corners with three equivalent K(2)Br3Cl3 octahedra, corners with three equivalent K(1)Cl6 octahedra, edges with three equivalent K(1)Cl6 octahedra, and edges with nine equivalent K(2)Br3Cl3 octahedra. The corner-sharing octahedra are not tilted. Br(1) is bonded to six equivalent K(2) atoms to form BrK6 octahedra that share corners with six equivalent Cl(1)K6 octahedra, edges with six equivalent Br(1)K6 octahedra, and edges with six equivalent Cl(1)K6 octahedra. The corner-sharing octahedral tilt angles are 3°. Cl(1) is bonded to three equivalent K(1) and three equivalent K(2) atoms to form ClK6 octahedra that share corners with three equivalent Br(1)K6 octahedra, corners with three equivalent Cl(1)K6 octahedra, edges with three equivalent Br(1)K6 octahedra, and edges with nine equivalent Cl(1)K6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°.
K3BrCl2 is Caswellsilverite-like structured and crystallizes in the trigonal P-3m1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to six equivalent Cl(1) atoms to form KCl6 octahedra that share corners with six equivalent K(2)Br3Cl3 octahedra, edges with six equivalent K(2)Br3Cl3 octahedra, and edges with six equivalent K(1)Cl6 octahedra. The corner-sharing octahedra are not tilted. All K(1)-Cl(1) bond lengths are 3.17 Å. In the second K site, K(2) is bonded to three equivalent Br(1) and three equivalent Cl(1) atoms to form KBr3Cl3 octahedra that share corners with three equivalent K(2)Br3Cl3 octahedra, corners with three equivalent K(1)Cl6 octahedra, edges with three equivalent K(1)Cl6 octahedra, and edges with nine equivalent K(2)Br3Cl3 octahedra. The corner-sharing octahedra are not tilted. All K(2)-Br(1) bond lengths are 3.27 Å. All K(2)-Cl(1) bond lengths are 3.16 Å. Br(1) is bonded to six equivalent K(2) atoms to form BrK6 octahedra that share corners with six equivalent Cl(1)K6 octahedra, edges with six equivalent Br(1)K6 octahedra, and edges with six equivalent Cl(1)K6 octahedra. The corner-sharing octahedral tilt angles are 3°. Cl(1) is bonded to three equivalent K(1) and three equivalent K(2) atoms to form ClK6 octahedra that share corners with three equivalent Br(1)K6 octahedra, corners with three equivalent Cl(1)K6 octahedra, edges with three equivalent Br(1)K6 octahedra, and edges with nine equivalent Cl(1)K6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°.