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DOE OSTI · 1284133

Materials Data on Sr7Al12O25 by Materials Project

Abstract

Sr7Al12O25 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are nine inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–3.00 Å. In the second Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–3.01 Å. In the third Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.74 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are one shorter (2.12 Å) and three longer (2.54 Å) Sr–O bond lengths. In the fifth Sr2+ site, Sr2+ is bonded to four O2- atoms to form distorted SrO4 trigonal pyramids that share corners with three equivalent AlO4 tetrahedra and corners with three equivalent AlO4 trigonal pyramids. There are one shorter (2.12 Å) and three longer (2.54 Å) Sr–O bond lengths. In the sixth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.75 Å. In the seventh Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–3.01 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.75 Å. In the ninth Sr2+ site, Sr2+ is bonded to four O2- atoms to form distorted SrO4 trigonal pyramids that share corners with three equivalent AlO4 tetrahedra and corners with three equivalent AlO4 trigonal pyramids. There are one shorter (2.12 Å) and three longer (2.53 Å) Sr–O bond lengths. There are twelve inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra, a cornercorner with one SrO4 trigonal pyramid, and corners with two equivalent AlO4 trigonal pyramids. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 trigonal pyramids. There are a spread of Al–O bond distances ranging from 1.77–1.85 Å. In the fifth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the sixth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the seventh Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 trigonal pyramids that share corners with four AlO4 tetrahedra and a cornercorner with one SrO4 trigonal pyramid. There are a spread of Al–O bond distances ranging from 1.77–1.85 Å. In the eighth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the ninth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the tenth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 trigonal pyramids that share corners with four AlO4 tetrahedra and a cornercorner with one SrO4 trigonal pyramid. There are a spread of Al–O bond distances ranging from 1.77–1.85 Å. In the eleventh Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the twelfth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra, a cornercorner with one SrO4 trigonal pyramid, and corners with two equivalent AlO4 trigonal pyramids. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. There are twenty-seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+ and two Al3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the fifth O2- site, O2- is bonded in a distorted tetrahedral geometry to two Sr2+ and two Al3+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and two Al3+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+ and two Al3+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the thirteenth O2- site, O2- is bonded in a single-bond geometry to one Sr2+ atom. In the fourteenth O2- site, O2- is bonded in a single-bond geometry to one Sr2+ atom. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted tetrahedral geometry to two Sr2+ and two Al3+ atoms. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twentieth O2- site, O2- is bonded in a distorted tetrahedral geometry to two Sr2+ and two Al3+ atoms. In the twenty-first O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and two Al3+ atoms. In the twenty-second O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twenty-fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twenty-fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+ and two Al3+ atoms. In the twenty-sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two Al3+ atoms. In the twenty-seventh O2- site, O2- is bonded in a single-bond geometry to one Sr2+ atom.

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2020-05-02. Materials Data on Sr7Al12O25 by Materials Project. https://doi.org/10.17188/1284133

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