Materials Data on K2TaF7 by Materials Project

Abstract

K2TaF7 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 11-coordinate geometry to eleven F1- atoms. There are a spread of K–F bond distances ranging from 2.72–3.08 Å. In the second K1+ site, K1+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of K–F bond distances ranging from 2.77–3.26 Å. Ta5+ is bonded in a distorted pentagonal bipyramidal geometry to seven F1- atoms. There are a spread of Ta–F bond distances ranging from 1.97–2.00 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to three equivalent K1+ and one Ta5+ atom. In the second F1- site, F1- is bonded in a 1-coordinate geometry to three K1+ and one Ta5+ atom. In the third F1- site, F1- is bonded in a 1-coordinate geometry to three K1+ and one Ta5+ atom. In the fourth F1- site, F1- is bonded in a 1-coordinate geometry to three K1+ and one Ta5+ atom.