Materials Data on Fe2P2H4O9 by Materials Project
Fe2P2H4O9 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with five PO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.05–2.23 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with five PO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.10–2.25 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 five FeO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–62°. 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 five FeO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–58°. There are a spread of P–O bond distances ranging from 1.53–1.63 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted water-like geometry to one Fe2+ and two H1+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to one Fe2+ and two H1+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Fe2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Fe2+ and one P5+ atom.