Materials Data on Na4Cr2P(CO4)4 by Materials Project

Abstract

Na4Cr2P(CO4)4 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with four equivalent NaO6 octahedra, edges with two equivalent CrO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 59–86°. There are a spread of Na–O bond distances ranging from 2.35–2.50 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with four equivalent NaO6 octahedra, edges with two equivalent CrO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 59–86°. There are a spread of Na–O bond distances ranging from 2.34–2.56 Å. Cr+3.50+ is bonded to six O2- atoms to form CrO6 octahedra that share edges with four NaO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.02–2.04 Å. C4+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.29 Å) and two longer (1.30 Å) C–O bond length. P5+ is bonded to four equivalent O2- atoms to form PO4 tetrahedra that share edges with four NaO6 octahedra. All P–O bond lengths are 1.55 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Na1+ and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Cr+3.50+, and one C4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Cr+3.50+, and one C4+ atom. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Cr+3.50+, and one C4+ atom.