Materials Data on Fe3(AsO8)2 by Materials Project

Fe3(AsO8)2 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one Fe3(AsO8)2 sheet oriented in the (0, -1, 1) direction. there are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with two equivalent AsO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.89–2.11 Å. In the second Fe site, Fe is bonded to six O atoms to form distorted FeO6 octahedra that share corners with four equivalent AsO4 tetrahedra and an edgeedge with one FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.13 Å. As is bonded to four O atoms to form AsO4 tetrahedra that share corners with five FeO6 octahedra. The corner-sharing octahedra tilt angles range from 36–58°. There are a spread of As–O bond distances ranging from 1.71–1.76 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to one Fe and one O atom. The O–O bond length is 1.30 Å. In the second O site, O is bonded in a 2-coordinate geometry to one Fe and one O atom. The O–O bond length is 1.32 Å. In the third O site, O is bonded in a 2-coordinate geometry to one Fe and one O atom. In the fourth O site, O is bonded in a 2-coordinate geometry to one Fe and one O atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Fe and one As atom. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Fe and one As atom. In the seventh O site, O is bonded in a bent 120 degrees geometry to one Fe and one As atom. In the eighth O site, O is bonded in a distorted T-shaped geometry to two equivalent Fe and one As atom.