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DOE OSTI · 1709462

Materials Data on Pr9Ga5Se21 by Materials Project

Abstract

Pr9Ga5Se21 crystallizes in the trigonal R3 space group. The structure is three-dimensional. there are six inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Pr–Se bond distances ranging from 3.01–3.17 Å. In the second Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.98–3.37 Å. In the third Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.97–3.27 Å. In the fourth Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.98–3.21 Å. In the fifth Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Pr–Se bond distances ranging from 2.99–3.36 Å. In the sixth Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Pr–Se bond distances ranging from 3.00–3.29 Å. There are six inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded in a tetrahedral geometry to four Se2- atoms. There are a spread of Ga–Se bond distances ranging from 2.39–2.44 Å. In the second Ga3+ site, Ga3+ is bonded in a tetrahedral geometry to four Se2- atoms. There are a spread of Ga–Se bond distances ranging from 2.39–2.44 Å. In the third Ga3+ site, Ga3+ is bonded in an octahedral geometry to six Se2- atoms. There are three shorter (2.64 Å) and three longer (2.73 Å) Ga–Se bond lengths. In the fourth Ga3+ site, Ga3+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are three shorter (2.46 Å) and three longer (3.06 Å) Ga–Se bond lengths. In the fifth Ga3+ site, Ga3+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are three shorter (2.45 Å) and three longer (3.09 Å) Ga–Se bond lengths. In the sixth Ga3+ site, Ga3+ is bonded in an octahedral geometry to six Se2- atoms. There are three shorter (2.65 Å) and three longer (2.72 Å) Ga–Se bond lengths. There are fourteen inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to four Pr3+ and one Ga3+ atom. In the second Se2- site, Se2- is bonded to three Pr3+ and two Ga3+ atoms to form distorted SePr3Ga2 square pyramids that share corners with three SePr3Ga tetrahedra, a cornercorner with one SePr3Ga trigonal pyramid, edges with two equivalent SePr3Ga trigonal pyramids, and faces with two equivalent SePr3Ga2 square pyramids. In the third Se2- site, Se2- is bonded to three Pr3+ and one Ga3+ atom to form distorted SePr3Ga trigonal pyramids that share a cornercorner with one SePr3Ga2 square pyramid, corners with three SePr3Ga tetrahedra, edges with two equivalent SePr3Ga2 square pyramids, and edges with two equivalent SePr3Ga trigonal pyramids. In the fourth Se2- site, Se2- is bonded to three Pr3+ and two Ga3+ atoms to form distorted SePr3Ga2 square pyramids that share corners with three SePr3Ga tetrahedra, a cornercorner with one SePr3Ga trigonal pyramid, edges with two equivalent SePr3Ga trigonal pyramids, and faces with two equivalent SePr3Ga2 square pyramids. In the fifth Se2- site, Se2- is bonded to three Pr3+ and one Ga3+ atom to form distorted SePr3Ga trigonal pyramids that share a cornercorner with one SePr3Ga2 square pyramid, corners with three SePr3Ga tetrahedra, edges with two equivalent SePr3Ga2 square pyramids, and edges with two equivalent SePr3Ga trigonal pyramids. In the sixth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Pr3+ and one Ga3+ atom. In the seventh Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Pr3+ and one Ga3+ atom. In the eighth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Pr3+ and one Ga3+ atom. In the ninth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Pr3+ and one Ga3+ atom. In the tenth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Pr3+ and one Ga3+ atom. In the eleventh Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Pr3+ and one Ga3+ atom. In the twelfth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Pr3+ and one Ga3+ atom. In the thirteenth Se2- site, Se2- is bonded to three Pr3+ and one Ga3+ atom to form distorted SePr3Ga tetrahedra that share corners with three SePr3Ga2 square pyramids and corners with three SePr3Ga trigonal pyramids. In the fourteenth Se2- site, Se2- is bonded to three Pr3+ and one Ga3+ atom to form distorted SePr3Ga tetrahedra that share corners with three SePr3Ga2 square pyramids and corners with three SePr3Ga trigonal pyramids.

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2020-04-29. Materials Data on Pr9Ga5Se21 by Materials Project. https://doi.org/10.17188/1709462

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