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DOE OSTI · 1268282

Materials Data on Pr7BP2O17 by Materials Project

Abstract

Pr7BP2O17 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are seven inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded to seven O2- atoms to form distorted PrO7 pentagonal bipyramids that share corners with three PO4 tetrahedra and an edgeedge with one PrO7 pentagonal bipyramid. There are a spread of Pr–O bond distances ranging from 2.31–2.59 Å. In the second Pr3+ site, Pr3+ is bonded to seven O2- atoms to form distorted PrO7 pentagonal bipyramids that share corners with two equivalent PO4 tetrahedra and an edgeedge with one PrO7 pentagonal bipyramid. There are a spread of Pr–O bond distances ranging from 2.35–2.62 Å. In the third Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.37–2.70 Å. In the fourth Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Pr–O bond distances ranging from 2.37–2.63 Å. In the fifth Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.30–2.82 Å. In the sixth Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.28–2.89 Å. In the seventh Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Pr–O bond distances ranging from 2.34–2.78 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.38–1.42 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent PrO7 pentagonal bipyramids. There is three shorter (1.55 Å) and one longer (1.57 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three PrO7 pentagonal bipyramids. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. There are seventeen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Pr3+ and one B3+ atom. In the second O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of distorted corner and edge-sharing OPr4 tetrahedra. In the third O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three Pr3+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Pr3+ and one P5+ atom. In the sixth O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the seventh O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one B3+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two Pr3+ and one P5+ atom. In the eleventh O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the twelfth O2- site, O2- is bonded in a distorted single-bond geometry to three Pr3+ and one B3+ atom. In the thirteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Pr3+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the fifteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Pr3+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Pr3+ and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one P5+ atom.

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2020-05-30. Materials Data on Pr7BP2O17 by Materials Project. https://doi.org/10.17188/1268282

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