Materials Data on Rb3(FeSe2)2 by Materials Project
Rb3(FeSe2)2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded to six Se2- atoms to form RbSe6 octahedra that share corners with eight equivalent FeSe4 tetrahedra, edges with two equivalent FeSe4 tetrahedra, and faces with two equivalent RbSe6 octahedra. There are a spread of Rb–Se bond distances ranging from 3.39–3.54 Å. In the second Rb1+ site, Rb1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Rb–Se bond distances ranging from 3.39–4.02 Å. Fe+2.50+ is bonded to four Se2- atoms to form FeSe4 tetrahedra that share corners with four equivalent RbSe6 octahedra, an edgeedge with one RbSe6 octahedra, and edges with two equivalent FeSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 21–63°. There are a spread of Fe–Se bond distances ranging from 2.40–2.47 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to four equivalent Rb1+ and two equivalent Fe+2.50+ atoms. In the second Se2- site, Se2- is bonded in a 8-coordinate geometry to six Rb1+ and two equivalent Fe+2.50+ atoms. In the third Se2- site, Se2- is bonded in a 7-coordinate geometry to five Rb1+ and two equivalent Fe+2.50+ atoms.