DOE OSTI2020
Fe3C7O19 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two Fe3C7O19 clusters. there are three inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form distorted FeO6 octahedra that share a cornercorner with one FeO5 square pyramid and a cornercorner with one FeO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.93–2.46 Å. In the second Fe site, Fe is bonded to four O atoms to form distorted FeO4 tetrahedra that share a cornercorner with one FeO6 octahedra and a cornercorner with one FeO5 square pyramid. The corner-sharing octahedral tilt angles are 60°. There are a spread of Fe–O bond distances ranging from 1.97–2.36 Å. In the third Fe site, Fe is bonded to five O atoms to form distorted FeO5 square pyramids that share a cornercorner with one FeO6 octahedra and a cornercorner with one FeO4 tetrahedra. The corner-sharing octahedral tilt angles are 64°. There are a spread of Fe–O bond distances ranging from 2.03–2.19 Å. There are seven inequivalent C sites. In the first C site, C is bonded in a distorted bent 150 degrees geometry to two O atoms. There is one shorter (1.24 Å) and one longer (1.25 Å) C–O bond length. In the second C site, C is bonded in a linear geometry to two O atoms. There is one shorter (1.16 Å) and one longer (1.19 Å) C–O bond length. In the third C site, C is bonded in a linear geometry to two O atoms. There is one shorter (1.17 Å) and one longer (1.19 Å) C–O bond length. In the fourth C site, C is bonded in a distorted bent 150 degrees geometry to two O atoms. There is one shorter (1.24 Å) and one longer (1.25 Å) C–O bond length. In the fifth C site, C is bonded in a linear geometry to two O atoms. There is one shorter (1.17 Å) and one longer (1.18 Å) C–O bond length. In the sixth C site, C is bonded in a linear geometry to two O atoms. There is one shorter (1.17 Å) and one longer (1.18 Å) C–O bond length. In the seventh C site, C is bonded in a linear geometry to two O atoms. There is one shorter (1.16 Å) and one longer (1.19 Å) C–O bond length. There are nineteen inequivalent O sites. In the first O site, O is bonded in a distorted bent 150 degrees geometry to one Fe and one C atom. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Fe and one C atom. In the third O site, O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.34 Å. In the fourth O site, O is bonded in a single-bond geometry to one C atom. In the fifth O site, O is bonded in a bent 120 degrees geometry to one Fe and one C atom. In the sixth O site, O is bonded in a distorted single-bond geometry to one Fe and one C atom. In the seventh O site, O is bonded in a single-bond geometry to one C atom. In the eighth O site, O is bonded in a single-bond geometry to one C atom. In the ninth O site, O is bonded in a distorted single-bond geometry to one Fe and one O atom. In the tenth O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the eleventh O site, O is bonded in a distorted bent 120 degrees geometry to one Fe and one C atom. In the twelfth O site, O is bonded in a 1-coordinate geometry to one Fe and one O atom. The O–O bond length is 1.37 Å. In the thirteenth O site, O is bonded in a distorted bent 120 degrees geometry to one Fe and one C atom. In the fourteenth O site, O is bonded in a single-bond geometry to one C atom. In the fifteenth O site, O is bonded in a distorted bent 120 degrees geometry to one Fe and one C atom. In the sixteenth O site, O is bonded in a single-bond geometry to one C atom. In the seventeenth O site, O is bonded in a 2-coordinate geometry to one Fe and one C atom. In the eighteenth O site, O is bonded in a bent 120 degrees geometry to one Fe and one C atom. In the nineteenth O site, O is bonded in a 1-coordinate geometry to one Fe and one O atom.