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DOE OSTI · 1351476

Materials Data on SrMgP3N5O2 by Materials Project

Abstract

SrMgP3N5O2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Sr2+ is bonded in a 5-coordinate geometry to six N3- and three O2- atoms. There are a spread of Sr–N bond distances ranging from 2.63–3.24 Å. There are a spread of Sr–O bond distances ranging from 2.60–3.18 Å. Mg2+ is bonded to three N3- and three O2- atoms to form distorted MgN3O3 octahedra that share corners with five PN3O tetrahedra, an edgeedge with one MgN3O3 octahedra, and edges with two PN3O tetrahedra. There are a spread of Mg–N bond distances ranging from 2.10–2.37 Å. There are a spread of Mg–O bond distances ranging from 2.05–2.31 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four N3- atoms to form PN4 tetrahedra that share corners with three equivalent MgN3O3 octahedra and corners with four PN3O tetrahedra. The corner-sharing octahedra tilt angles range from 48–61°. There are a spread of P–N bond distances ranging from 1.63–1.65 Å. In the second P5+ site, P5+ is bonded to three N3- and one O2- atom to form PN3O tetrahedra that share a cornercorner with one MgN3O3 octahedra, corners with three PN4 tetrahedra, and an edgeedge with one MgN3O3 octahedra. The corner-sharing octahedral tilt angles are 62°. All P–N bond lengths are 1.63 Å. The P–O bond length is 1.58 Å. In the third P5+ site, P5+ is bonded to three N3- and one O2- atom to form PN3O tetrahedra that share a cornercorner with one MgN3O3 octahedra, corners with three PN4 tetrahedra, and an edgeedge with one MgN3O3 octahedra. The corner-sharing octahedral tilt angles are 58°. There is one shorter (1.63 Å) and two longer (1.65 Å) P–N bond length. The P–O bond length is 1.56 Å. There are five inequivalent N3- sites. In the first N3- site, N3- is bonded in a 3-coordinate geometry to two equivalent Sr2+ and two P5+ atoms. In the second N3- site, N3- is bonded in a 2-coordinate geometry to two equivalent Sr2+ and two P5+ atoms. In the third N3- site, N3- is bonded in a distorted trigonal planar geometry to one Mg2+ and two P5+ atoms. In the fourth N3- site, N3- is bonded in a 3-coordinate geometry to one Sr2+, one Mg2+, and two P5+ atoms. In the fifth N3- site, N3- is bonded in a 4-coordinate geometry to one Sr2+, one Mg2+, and two P5+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+, two equivalent Mg2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, one Mg2+, and one P5+ atom.

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2020-05-02. Materials Data on SrMgP3N5O2 by Materials Project. https://doi.org/10.17188/1351476

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36 MATERIALS SCIENCE↗