Materials Data on KBe2BO3F2 by Materials Project
KBe2BO3F2 crystallizes in the trigonal R32 space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six equivalent F1- atoms. All K–F bond lengths are 2.81 Å. Be2+ is bonded to three equivalent O2- and one F1- atom to form corner-sharing BeO3F tetrahedra. All Be–O bond lengths are 1.65 Å. The Be–F bond length is 1.54 Å. B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.38 Å. O2- is bonded in a trigonal planar geometry to two equivalent Be2+ and one B3+ atom. F1- is bonded in a distorted single-bond geometry to three equivalent K1+ and one Be2+ atom.