Materials Data on Na3CaPCO7 by Materials Project

Abstract

Na3CaCPO7 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.38–2.78 Å. In the second Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.37–2.95 Å. Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with four equivalent PO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.27–2.44 Å. C4+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.29 Å) and two longer (1.31 Å) C–O bond length. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent CaO6 octahedra. The corner-sharing octahedra tilt angles range from 46–63°. All P–O bond lengths are 1.56 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one C4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Ca2+, and one C4+ atom. In the third O2- site, O2- is bonded to three Na1+, one Ca2+, and one C4+ atom to form distorted corner-sharing ONa3CaC trigonal bipyramids. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Ca2+, and one P5+ atom. In the fifth O2- site, O2- is bonded to two equivalent Na1+, one Ca2+, and one P5+ atom to form distorted corner-sharing ONa2CaP tetrahedra. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Ca2+, and one P5+ atom.