Materials Data on KTa2PO8 by Materials Project

Abstract

KTa2PO8 crystallizes in the trigonal R3 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 2.98–3.41 Å. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with four TaO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 4–38°. There are a spread of Ta–O bond distances ranging from 1.90–2.09 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with four TaO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 4–39°. There are a spread of Ta–O bond distances ranging from 1.90–2.11 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four TaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–40°. There is two shorter (1.54 Å) and two longer (1.55 Å) P–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two Ta5+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two Ta5+ atoms. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Ta5+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two equivalent Ta5+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ta5+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ta5+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Ta5+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two equivalent Ta5+ atoms.