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DOE OSTI · 1654265

Materials Data on ZnFeAs4(Pb2O9)2 by Materials Project

Abstract

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.

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2020-07-15. Materials Data on ZnFeAs4(Pb2O9)2 by Materials Project. https://doi.org/10.17188/1654265

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