Materials Data on KAlF4 by Materials Project

Abstract

KAlF4 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. K1+ is bonded in a body-centered cubic geometry to eight equivalent F1- atoms. All K–F bond lengths are 2.90 Å. Al3+ is bonded to six F1- atoms to form corner-sharing AlF6 octahedra. The corner-sharing octahedral tilt angles are 23°. There is two shorter (1.79 Å) and four longer (1.85 Å) Al–F bond length. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to four equivalent K1+ and one Al3+ atom. In the second F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Al3+ atoms.