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DOE OSTI · 1687263

Materials Data on Mn2As2O7 by Materials Project

Abstract

Mn2As2O7 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to six O2- atoms to form distorted MnO6 pentagonal pyramids that share corners with six AsO4 tetrahedra and edges with three equivalent MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 2.16–2.39 Å. In the second Mn2+ site, Mn2+ is bonded to six O2- atoms to form distorted MnO6 octahedra that share corners with six AsO4 tetrahedra and edges with three equivalent MnO6 pentagonal pyramids. There are a spread of Mn–O bond distances ranging from 2.15–2.30 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 MnO6 octahedra, corners with three equivalent MnO6 pentagonal pyramids, and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–62°. 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 MnO6 octahedra, corners with three equivalent MnO6 pentagonal pyramids, and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–62°. There are a spread of As–O bond distances ranging from 1.71–1.76 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mn2+ and one As5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Mn2+ and one As5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two Mn2+ and one As5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mn2+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mn2+ and one As5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mn2+ and one As5+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two As5+ atoms.

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2020-05-03. Materials Data on Mn2As2O7 by Materials Project. https://doi.org/10.17188/1687263

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36 MATERIALS SCIENCE↗