Materials Data on KTa(PO4)2 by Materials Project
KTa(PO4)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. K1+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.97–3.21 Å. Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six equivalent PO4 tetrahedra. There is two shorter (1.95 Å) and four longer (1.99 Å) Ta–O bond length. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent TaO6 octahedra. The corner-sharing octahedra tilt angles range from 26–35°. There are a spread of P–O bond distances ranging from 1.49–1.58 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Ta5+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Ta5+ and one P5+ atom.