Materials Data on K3UF6 by Materials Project
K3UF6 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 4-coordinate geometry to four equivalent F1- atoms. All K–F bond lengths are 2.74 Å. In the second K1+ site, K1+ is bonded in a linear geometry to two equivalent F1- atoms. Both K–F bond lengths are 2.45 Å. U3+ is bonded in an octahedral geometry to six F1- atoms. There are two shorter (2.24 Å) and four longer (2.26 Å) U–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to two equivalent K1+ and one U3+ atom. In the second F1- site, F1- is bonded in a linear geometry to one K1+ and one U3+ atom.