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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
FePbAs2O8 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six AsO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.97–2.12 Å. Pb4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Pb–O bond distances ranging from 2.36–2.54 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 46–55°. There are a spread of As–O bond distances ranging from 1.70–1.76 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 41–57°. There are a spread of As–O bond distances ranging from 1.71–1.75 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Fe2+ and one As5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Fe2+, one Pb4+, and one As5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Fe2+, one Pb4+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to one Pb4+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe2+ and one As5+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Fe2+ and one As5+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Fe2+, one Pb4+, and one As5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Pb4+ and one As5+ atom.
FeZnAs4(Pb2O9)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent PbO6 octahedra, corners with four AsO4 tetrahedra, and edges with two equivalent ZnO6 octahedra. The corner-sharing octahedral tilt angles are 64°. There are a spread of Fe–O bond distances ranging from 1.82–2.06 Å. Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share corners with two equivalent PbO6 octahedra, corners with four AsO4 tetrahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 65°. There are a spread of Zn–O bond distances ranging from 1.99–2.16 Å. There are two inequivalent Pb3+ sites. In the first Pb3+ site, Pb3+ is bonded to six O2- atoms to form distorted PbO6 octahedra that share a cornercorner with one FeO6 octahedra, a cornercorner with one ZnO6 octahedra, and corners with six AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 64–65°. There are a spread of Pb–O bond distances ranging from 2.39–2.89 Å. In the second Pb3+ site, Pb3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Pb–O bond distances ranging from 2.46–2.78 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share a cornercorner with one FeO6 octahedra, a cornercorner with one ZnO6 octahedra, and corners with three equivalent PbO6 octahedra. The corner-sharing octahedra tilt angles range from 56–69°. There are a spread of As–O bond distances ranging from 1.69–1.76 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share a cornercorner with one FeO6 octahedra, a cornercorner with one ZnO6 octahedra, and corners with three equivalent PbO6 octahedra. The corner-sharing octahedra tilt angles range from 44–64°. There are a spread of As–O bond distances ranging from 1.71–1.74 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to one Pb3+ and one As5+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Zn2+, two Pb3+, and one As5+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe2+, two Pb3+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Pb3+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Fe2+, one Zn2+, and one As5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two Pb3+ and one As5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Pb3+ and one As5+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one Pb3+ and one As5+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Fe2+, one Zn2+, and one Pb3+ atom.
Fe2(AsO4)F crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are four inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four O2- and two F1- atoms to form distorted FeO4F2 pentagonal pyramids that share corners with four AsO4 tetrahedra, corners with two FeO4F trigonal bipyramids, edges with two equivalent FeO4F2 octahedra, and an edgeedge with one FeO4F trigonal bipyramid. There are a spread of Fe–O bond distances ranging from 2.13–2.16 Å. There are one shorter (2.17 Å) and one longer (2.31 Å) Fe–F bond lengths. In the second Fe3+ site, Fe3+ is bonded to four O2- and one F1- atom to form FeO4F trigonal bipyramids that share a cornercorner with one FeO4F2 octahedra, a cornercorner with one FeO4F2 pentagonal pyramid, corners with four AsO4 tetrahedra, corners with two equivalent FeO4F trigonal bipyramids, and an edgeedge with one FeO4F2 pentagonal pyramid. The corner-sharing octahedral tilt angles are 53°. There are a spread of Fe–O bond distances ranging from 2.11–2.17 Å. The Fe–F bond length is 2.01 Å. In the third Fe3+ site, Fe3+ is bonded to four O2- and two F1- atoms to form FeO4F2 octahedra that share corners with four AsO4 tetrahedra, corners with two FeO4F trigonal bipyramids, edges with two equivalent FeO4F2 pentagonal pyramids, and an edgeedge with one FeO4F trigonal bipyramid. There are a spread of Fe–O bond distances ranging from 2.10–2.18 Å. There are one shorter (2.16 Å) and one longer (2.19 Å) Fe–F bond lengths. In the fourth Fe3+ site, Fe3+ is bonded to four O2- and one F1- atom to form FeO4F trigonal bipyramids that share a cornercorner with one FeO4F2 octahedra, a cornercorner with one FeO4F2 pentagonal pyramid, corners with four AsO4 tetrahedra, corners with two equivalent FeO4F trigonal bipyramids, and an edgeedge with one FeO4F2 octahedra. The corner-sharing octahedral tilt angles are 51°. There are two shorter (2.10 Å) and two longer (2.12 Å) Fe–O bond lengths. The Fe–F bond length is 2.04 Å. There are two inequivalent As3+ sites. In the first As3+ site, As3+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent FeO4F2 octahedra, corners with two equivalent FeO4F2 pentagonal pyramids, and corners with four FeO4F trigonal bipyramids. The corner-sharing octahedra tilt angles range from 48–56°. There is one shorter (1.71 Å) and three longer (1.73 Å) As–O bond length. In the second As3+ site, As3+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent FeO4F2 octahedra, corners with two equivalent FeO4F2 pentagonal pyramids, and corners with four FeO4F trigonal bipyramids. The corner-sharing octahedra tilt angles range from 47–59°. There is two shorter (1.72 Å) and two longer (1.73 Å) As–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and one As3+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and one As3+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and one As3+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and one As3+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and one As3+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and one As3+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and one As3+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and one As3+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to three Fe3+ atoms. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to three Fe3+ atoms.