Materials Data on Rb2MnBr4 by Materials Project
Rb2MnBr4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Rb1+ is bonded in a 9-coordinate geometry to nine Br1- atoms. There are a spread of Rb–Br bond distances ranging from 3.48–3.84 Å. Mn2+ is bonded to six Br1- atoms to form corner-sharing MnBr6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.68 Å) and four longer (2.70 Å) Mn–Br bond lengths. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded to five equivalent Rb1+ and one Mn2+ atom to form distorted BrRb5Mn octahedra that share corners with seventeen BrRb5Mn octahedra, edges with eight equivalent BrRb5Mn octahedra, and faces with four equivalent BrRb4Mn2 octahedra. The corner-sharing octahedra tilt angles range from 0–55°. In the second Br1- site, Br1- is bonded to four equivalent Rb1+ and two equivalent Mn2+ atoms to form distorted BrRb4Mn2 octahedra that share corners with fourteen BrRb5Mn octahedra, edges with two equivalent BrRb4Mn2 octahedra, and faces with eight BrRb5Mn octahedra. The corner-sharing octahedra tilt angles range from 0–55°.