Materials Data on Fe2Mo4O7 by Materials Project
Fe2Mo4O7 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are eight inequivalent Mo2+ sites. In the first Mo2+ site, Mo2+ is bonded to five O2- atoms to form MoO5 square pyramids that share corners with three FeO4 tetrahedra, edges with two FeO6 octahedra, and edges with two equivalent MoO5 square pyramids. There are a spread of Mo–O bond distances ranging from 2.07–2.09 Å. In the second Mo2+ site, Mo2+ is bonded to five O2- atoms to form MoO5 square pyramids that share corners with three FeO4 tetrahedra, edges with two FeO6 octahedra, and edges with two equivalent MoO5 square pyramids. There are a spread of Mo–O bond distances ranging from 2.10–2.20 Å. In the third Mo2+ site, Mo2+ is bonded to five O2- atoms to form MoO5 square pyramids that share corners with three FeO4 tetrahedra, edges with two FeO6 octahedra, and edges with two equivalent MoO5 square pyramids. There are a spread of Mo–O bond distances ranging from 2.06–2.09 Å. In the fourth Mo2+ site, Mo2+ is bonded to five O2- atoms to form MoO5 square pyramids that share corners with three FeO4 tetrahedra, edges with two FeO6 octahedra, and edges with two equivalent MoO5 square pyramids. There are a spread of Mo–O bond distances ranging from 2.10–2.19 Å. In the fifth Mo2+ site, Mo2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Mo–O bond distances ranging from 2.15–2.19 Å. In the sixth Mo2+ site, Mo2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Mo–O bond distances ranging from 2.15–2.19 Å. In the seventh Mo2+ site, Mo2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are one shorter (2.14 Å) and three longer (2.19 Å) Mo–O bond lengths. In the eighth Mo2+ site, Mo2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Mo–O bond distances ranging from 2.15–2.19 Å. There are four inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with four FeO6 octahedra and corners with six MoO5 square pyramids. The corner-sharing octahedra tilt angles range from 59–60°. There are a spread of Fe–O bond distances ranging from 2.03–2.08 Å. In the second Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with four FeO6 octahedra and corners with six MoO5 square pyramids. The corner-sharing octahedra tilt angles range from 59–60°. There are a spread of Fe–O bond distances ranging from 2.03–2.08 Å. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four FeO4 tetrahedra, edges with two equivalent FeO6 octahedra, and edges with four MoO5 square pyramids. There are a spread of Fe–O bond distances ranging from 2.11–2.35 Å. In the fourth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four FeO4 tetrahedra, edges with two equivalent FeO6 octahedra, and edges with four MoO5 square pyramids. There are a spread of Fe–O bond distances ranging from 2.11–2.35 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to one Mo2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing OFe3Mo tetrahedra. In the second O2- site, O2- is bonded to one Mo2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing OFe3Mo trigonal pyramids. In the third O2- site, O2- is bonded to one Mo2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing OFe3Mo tetrahedra. In the fourth O2- site, O2- is bonded to one Mo2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing OFe3Mo trigonal pyramids. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mo2+ and one Fe3+ atom. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mo2+ and one Fe3+ atom. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mo2+ and one Fe3+ atom. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mo2+ and one Fe3+ atom. In the ninth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mo2+ and one Fe3+ atom. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mo2+ and one Fe3+ atom. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mo2+ and one Fe3+ atom. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mo2+ and one Fe3+ atom. In the thirteenth O2- site, O2- is bonded in a square co-planar geometry to four Mo2+ atoms. In the fourteenth O2- site, O2- is bonded in a square co-planar geometry to four Mo2+ atoms.