Materials Data on Rb2TaF7 by Materials Project

Abstract

Rb2TaF7 crystallizes in the monoclinic P2/c space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are four shorter (2.88 Å) and two longer (2.90 Å) Rb–F bond lengths. In the second Rb1+ site, Rb1+ is bonded to twelve F1- atoms to form distorted RbF12 cuboctahedra that share corners with four equivalent RbF12 cuboctahedra, faces with four equivalent RbF12 cuboctahedra, and faces with four equivalent TaF7 pentagonal bipyramids. There are a spread of Rb–F bond distances ranging from 2.98–3.11 Å. Ta5+ is bonded to seven F1- atoms to form distorted TaF7 pentagonal bipyramids that share faces with four equivalent RbF12 cuboctahedra. There are a spread of Ta–F bond distances ranging from 1.97–2.03 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to three Rb1+ and one Ta5+ atom. In the second F1- site, F1- is bonded in a distorted single-bond geometry to three Rb1+ and one Ta5+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to four equivalent Rb1+ and one Ta5+ atom. In the fourth F1- site, F1- is bonded in a distorted single-bond geometry to one Rb1+ and one Ta5+ atom.