Materials Data on K2NbO3F5 by Materials Project
K2NbO3F5 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded in a 9-coordinate geometry to four O and five F atoms. There are a spread of K–O bond distances ranging from 2.91–3.04 Å. There are a spread of K–F bond distances ranging from 2.60–2.94 Å. In the second K site, K is bonded in a 10-coordinate geometry to ten F atoms. There are a spread of K–F bond distances ranging from 2.89–3.11 Å. In the third K site, K is bonded in a 10-coordinate geometry to ten F atoms. There are a spread of K–F bond distances ranging from 2.79–3.18 Å. Nb is bonded in a pentagonal bipyramidal geometry to two O and five F atoms. Both Nb–O bond lengths are 1.97 Å. There are a spread of Nb–F bond distances ranging from 1.99–2.06 Å. There are four inequivalent O sites. In the first O site, O is bonded in a 1-coordinate geometry to one K, one Nb, and one O atom. The O–O bond length is 1.47 Å. In the second O site, O is bonded in a 1-coordinate geometry to one K, one Nb, and one O atom. In the third O site, O is bonded in a distorted single-bond geometry to two equivalent K and one O atom. The O–O bond length is 1.25 Å. In the fourth O site, O is bonded in a distorted T-shaped geometry to two equivalent K and one O atom. There are five inequivalent F sites. In the first F site, F is bonded in a 4-coordinate geometry to three K and one Nb atom. In the second F site, F is bonded in a distorted single-bond geometry to three K and one Nb atom. In the third F site, F is bonded in a 4-coordinate geometry to three K and one Nb atom. In the fourth F site, F is bonded in a distorted single-bond geometry to three K and one Nb atom. In the fifth F site, F is bonded in a 4-coordinate geometry to three K and one Nb atom.