DOI: 10.17188/1205554
title: Materials Data on Rb4P21I by Materials Project

description: Rb4P21I crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 8-coordinate geometry to seven P+0.14- and one I1- atom. There are a spread of Rb–P bond distances ranging from 3.39–3.88 Å. The Rb–I bond length is 3.94 Å. In the second Rb1+ site, Rb1+ is bonded in a 8-coordinate geometry to six P+0.14- and two equivalent I1- atoms. There are a spread of Rb–P bond distances ranging from 3.61–3.91 Å. Both Rb–I bond lengths are 3.90 Å. There are eight inequivalent P+0.14- sites. In the first P+0.14- site, P+0.14- is bonded in a 5-coordinate geometry to two equivalent Rb1+ and three P+0.14- atoms. There are one shorter (2.15 Å) and two longer (2.24 Å) P–P bond lengths. In the second P+0.14- site, P+0.14- is bonded to one Rb1+ and three P+0.14- atoms to form PRbP3 tetrahedra that share a cornercorner with one IRb6 pentagonal pyramid, corners with two equivalent PRbP3 tetrahedra, and corners with six PRbP3 trigonal pyramids. There are one shorter (2.16 Å) and two longer (2.24 Å) P–P bond lengths. In the third P+0.14- site, P+0.14- is bonded to one Rb1+ and three P+0.14- atoms to form PRbP3 tetrahedra that share a cornercorner with one IRb6 pentagonal pyramid, corners with four PRbP3 tetrahedra, and corners with four PRbP3 trigonal pyramids. There are one shorter (2.15 Å) and two longer (2.26 Å) P–P bond lengths. In the fourth P+0.14- site, P+0.14- is bonded to one Rb1+ and three P+0.14- atoms to form PRbP3 tetrahedra that share corners with two equivalent IRb6 pentagonal pyramids, corners with three PRbP3 tetrahedra, corners with four PRb2P2 trigonal pyramids, and an edgeedge with one PRbP3 trigonal pyramid. There are one shorter (2.20 Å) and one longer (2.27 Å) P–P bond lengths. In the fifth P+0.14- site, P+0.14- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Rb1+ and two equivalent P+0.14- atoms. In the sixth P+0.14- site, P+0.14- is bonded to two equivalent Rb1+ and two P+0.14- atoms to form distorted PRb2P2 trigonal pyramids that share corners with two equivalent IRb6 pentagonal pyramids, corners with four equivalent PRbP3 tetrahedra, corners with ten PRb2P2 trigonal pyramids, and an edgeedge with one IRb6 pentagonal pyramid. In the seventh P+0.14- site, P+0.14- is bonded to one Rb1+ and three P+0.14- atoms to form PRbP3 trigonal pyramids that share a cornercorner with one IRb6 pentagonal pyramid, corners with four PRbP3 tetrahedra, and corners with four PRb2P2 trigonal pyramids. The P–P bond length is 2.24 Å. In the eighth P+0.14- site, P+0.14- is bonded to one Rb1+ and three P+0.14- atoms to form distorted PRbP3 trigonal pyramids that share corners with two equivalent IRb6 pentagonal pyramids, corners with three PRbP3 tetrahedra, corners with six PRb2P2 trigonal pyramids, and an edgeedge with one PRbP3 tetrahedra. The P–P bond length is 2.26 Å. I1- is bonded to six Rb1+ atoms to form distorted IRb6 pentagonal pyramids that share corners with twelve PRbP3 tetrahedra, corners with sixteen PRb2P2 trigonal pyramids, edges with two equivalent IRb6 pentagonal pyramids, and edges with two equivalent PRb2P2 trigonal pyramids.