Materials Data on Rb2V2Si8O21 by Materials Project
Rb2V2Si8O21 crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of Rb–O bond distances ranging from 3.15–3.41 Å. In the second Rb1+ site, Rb1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Rb–O bond distances ranging from 2.88–3.30 Å. There are two inequivalent V4+ sites. In the first V4+ site, V4+ is bonded to five O2- atoms to form distorted VO5 trigonal bipyramids that share corners with four SiO4 tetrahedra and an edgeedge with one VO5 square pyramid. There are a spread of V–O bond distances ranging from 1.65–2.05 Å. In the second V4+ site, V4+ is bonded to five O2- atoms to form distorted VO5 square pyramids that share corners with four SiO4 tetrahedra and an edgeedge with one VO5 trigonal bipyramid. There are a spread of V–O bond distances ranging from 1.64–2.06 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three SiO4 tetrahedra and a cornercorner with one VO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one VO5 square pyramid and corners with three SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There is two shorter (1.62 Å) and two longer (1.63 Å) Si–O bond length. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one VO5 square pyramid, corners with three SiO4 tetrahedra, and a cornercorner with one VO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Rb1+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a single-bond geometry to one V4+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Rb1+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Rb1+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two V4+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Si4+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Rb1+ and two Si4+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one V4+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to one Rb1+ and one V4+ atom. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Rb1+ and two Si4+ atoms. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Rb1+ and two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Rb1+, one V4+, and one Si4+ atom.