Materials Data on Cs2CaP2O7 by Materials Project

Abstract

Cs2CaP2O7 is Pb(Zr_(1-x)Ti_x)O3-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Cs–O bond distances ranging from 3.12–3.62 Å. In the second Cs1+ site, Cs1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Cs–O bond distances ranging from 3.12–3.60 Å. Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.33–2.45 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 CaO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 16–26°. There are a spread of P–O bond distances ranging from 1.53–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent CaO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 10–23°. There is three shorter (1.53 Å) and one longer (1.63 Å) P–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Cs1+, one Ca2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to three Cs1+, one Ca2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Cs1+, one Ca2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Cs1+, one Ca2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a linear geometry to one Cs1+ and two P5+ atoms.