Materials Data on KYP2O7 by Materials Project
KYP2O7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.82–3.19 Å. Y3+ is bonded to six O2- atoms to form YO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Y–O bond distances ranging from 2.22–2.31 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent YO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 18–52°. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent YO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 13–52°. There is three shorter (1.53 Å) and one longer (1.64 Å) P–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Y3+, and one P5+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Y3+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+, one Y3+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to one Y3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+, one Y3+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Y3+, and one P5+ atom.