Materials Data on K2EuF5 by Materials Project
K2EuF5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of K–F bond distances ranging from 2.73–2.96 Å. Eu3+ is bonded to seven F1- atoms to form distorted edge-sharing EuF7 pentagonal bipyramids. There are a spread of Eu–F bond distances ranging from 2.28–2.39 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a 5-coordinate geometry to four equivalent K1+ and one Eu3+ atom. In the second F1- site, F1- is bonded in a 1-coordinate geometry to four equivalent K1+ and one Eu3+ atom. In the third F1- site, F1- is bonded in a 5-coordinate geometry to four equivalent K1+ and one Eu3+ atom. In the fourth F1- site, F1- is bonded to two equivalent K1+ and two equivalent Eu3+ atoms to form a mixture of distorted edge and corner-sharing FK2Eu2 tetrahedra.