Materials Data on NaFePCO7 by Materials Project
NaFeCPO7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.30–2.74 Å. Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four equivalent PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.94–2.16 Å. C is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.25 Å) and two longer (1.30 Å) C–O bond length. P is bonded to four O atoms to form PO4 tetrahedra that share corners with four equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 39–42°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a distorted bent 150 degrees geometry to one Na and one C atom. In the second O site, O is bonded in a 3-coordinate geometry to one Na, one Fe, and one C atom. In the third O site, O is bonded in a 3-coordinate geometry to one Na, one Fe, and one C atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the fifth O site, O is bonded in a 3-coordinate geometry to one Na, one Fe, and one P atom. In the sixth O site, O is bonded in a 3-coordinate geometry to one Na, one Fe, and one P atom. In the seventh O site, O is bonded in a 3-coordinate geometry to one Na, one Fe, and one P atom.