Materials Data on KTa(BO3)2 by Materials Project

Abstract

KTaB2O6 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.90–3.39 Å. Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are a spread of Ta–O bond distances ranging from 1.86–2.10 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.36 Å) and one longer (1.41 Å) B–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Ta5+, and one B3+ atom. In the second O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+, one Ta5+, and one B3+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent K1+ and two equivalent B3+ atoms.