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DOE OSTI · 1275769

Materials Data on NaPr4I7N2 by Materials Project

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Abstract

NaPr4N2I7 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. Na1+ is bonded in a distorted octahedral geometry to six I1- atoms. There are a spread of Na–I bond distances ranging from 3.08–3.52 Å. There are four inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and four I1- atoms. Both Pr–N bond lengths are 2.33 Å. There are a spread of Pr–I bond distances ranging from 3.18–3.47 Å. In the second Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and four I1- atoms. Both Pr–N bond lengths are 2.34 Å. There are a spread of Pr–I bond distances ranging from 3.15–3.42 Å. In the third Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and four I1- atoms. There are one shorter (2.35 Å) and one longer (2.36 Å) Pr–N bond lengths. There are a spread of Pr–I bond distances ranging from 3.24–3.76 Å. In the fourth Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to two N3- and four I1- atoms. Both Pr–N bond lengths are 2.36 Å. There are a spread of Pr–I bond distances ranging from 3.24–3.73 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to four Pr3+ atoms to form edge-sharing NPr4 tetrahedra. In the second N3- site, N3- is bonded to four Pr3+ atoms to form edge-sharing NPr4 tetrahedra. There are seven inequivalent I1- sites. In the first I1- site, I1- is bonded in a 3-coordinate geometry to one Na1+ and two Pr3+ atoms. In the second I1- site, I1- is bonded in a 4-coordinate geometry to one Na1+ and three Pr3+ atoms. In the third I1- site, I1- is bonded in a 2-coordinate geometry to two Pr3+ atoms. In the fourth I1- site, I1- is bonded in a 4-coordinate geometry to one Na1+ and three Pr3+ atoms. In the fifth I1- site, I1- is bonded in a 3-coordinate geometry to one Na1+ and two Pr3+ atoms. In the sixth I1- site, I1- is bonded in a 3-coordinate geometry to one Na1+ and two Pr3+ atoms. In the seventh I1- site, I1- is bonded in a distorted T-shaped geometry to one Na1+ and two Pr3+ atoms.

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36 MATERIALS SCIENCEcrystal structureI-N-Na-PrNaPr4I7N2

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2020-05-02. Materials Data on NaPr4I7N2 by Materials Project. https://doi.org/10.17188/1275769

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36 MATERIALS SCIENCE↗