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DOE OSTI · 1285783

Materials Data on Ni5Te4(BrO6)2 by Materials Project

Abstract

Ni5(TeO3)4Br2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two Ni5(TeO3)4Br2 sheets oriented in the (1, 0, 0) direction. there are three inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded to six O2- atoms to form distorted NiO6 octahedra that share corners with three NiO6 octahedra, an edgeedge with one NiO6 octahedra, and a faceface with one NiBrO5 octahedra. The corner-sharing octahedra tilt angles range from 55–73°. There are a spread of Ni–O bond distances ranging from 2.04–2.27 Å. In the second Ni2+ site, Ni2+ is bonded to five O2- and one Br1- atom to form a mixture of distorted face and corner-sharing NiBrO5 octahedra. The corner-sharing octahedra tilt angles range from 55–73°. There are a spread of Ni–O bond distances ranging from 2.04–2.16 Å. The Ni–Br bond length is 2.60 Å. In the third Ni2+ site, Ni2+ is bonded to six O2- atoms to form distorted NiO6 octahedra that share corners with two equivalent NiO6 octahedra, edges with two equivalent NiO6 octahedra, and faces with two equivalent NiBrO5 octahedra. The corner-sharing octahedral tilt angles are 65°. There are a spread of Ni–O bond distances ranging from 2.02–2.35 Å. There are two inequivalent Te4+ sites. In the first Te4+ site, Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–1.93 Å. In the second Te4+ site, Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.86–1.95 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted T-shaped geometry to two Ni2+ and one Te4+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to two Ni2+ and one Te4+ atom. In the third O2- site, O2- is bonded to three Ni2+ and one Te4+ atom to form a mixture of distorted edge and corner-sharing ONi3Te trigonal pyramids. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ni2+ and one Te4+ atom. In the fifth O2- site, O2- is bonded to three Ni2+ and one Te4+ atom to form a mixture of edge and corner-sharing ONi3Te tetrahedra. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Ni2+ and one Te4+ atom. Br1- is bonded in a distorted single-bond geometry to one Ni2+ atom.

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2020-08-03. Materials Data on Ni5Te4(BrO6)2 by Materials Project. https://doi.org/10.17188/1285783

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