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DOE OSTI · 1207958

Materials Data on Nd6Al7Si5N3O25 by Materials Project

Abstract

Nd6Al7Si5N3O25 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded in a 8-coordinate geometry to two N3- and six O2- atoms. There are one shorter (2.32 Å) and one longer (2.59 Å) Nd–N bond lengths. There are a spread of Nd–O bond distances ranging from 2.31–2.82 Å. In the second Nd3+ site, Nd3+ is bonded in a 8-coordinate geometry to one N3- and seven O2- atoms. The Nd–N bond length is 2.52 Å. There are a spread of Nd–O bond distances ranging from 2.28–2.86 Å. In the third Nd3+ site, Nd3+ is bonded in a 7-coordinate geometry to one N3- and six O2- atoms. The Nd–N bond length is 2.61 Å. There are a spread of Nd–O bond distances ranging from 2.26–2.68 Å. In the fourth Nd3+ site, Nd3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Nd–O bond distances ranging from 2.30–2.82 Å. In the fifth Nd3+ site, Nd3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Nd–O bond distances ranging from 2.23–2.90 Å. In the sixth Nd3+ site, Nd3+ is bonded in a 7-coordinate geometry to one N3- and seven O2- atoms. The Nd–N bond length is 2.68 Å. There are a spread of Nd–O bond distances ranging from 2.24–2.99 Å. There are seven inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two AlNO5 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–62°. There are a spread of Al–O bond distances ranging from 1.74–1.84 Å. In the second Al3+ site, Al3+ is bonded to one N3- and five O2- atoms to form AlNO5 octahedra that share a cornercorner with one SiN2O2 tetrahedra, corners with three AlO4 tetrahedra, and an edgeedge with one AlNO4 trigonal bipyramid. The Al–N bond length is 1.96 Å. There are a spread of Al–O bond distances ranging from 1.89–2.08 Å. In the third Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share a cornercorner with one SiN2O2 tetrahedra, corners with three AlO4 tetrahedra, and a cornercorner with one AlNO4 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.88–2.03 Å. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form distorted AlO4 tetrahedra that share corners with two AlNO5 octahedra and corners with two SiNO3 tetrahedra. The corner-sharing octahedra tilt angles range from 61–66°. There are a spread of Al–O bond distances ranging from 1.74–1.85 Å. In the fifth Al3+ site, Al3+ is bonded to one N3- and four O2- atoms to form AlNO4 trigonal bipyramids that share a cornercorner with one AlO6 octahedra, a cornercorner with one AlNO3 tetrahedra, corners with two SiO4 tetrahedra, and an edgeedge with one AlNO5 octahedra. The corner-sharing octahedral tilt angles are 61°. The Al–N bond length is 1.98 Å. There are a spread of Al–O bond distances ranging from 1.80–2.09 Å. In the sixth Al3+ site, Al3+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Al–O bond distances ranging from 1.75–1.84 Å. In the seventh Al3+ site, Al3+ is bonded to one N3- and three O2- atoms to form distorted AlNO3 tetrahedra that share corners with two AlNO5 octahedra, corners with two SiO4 tetrahedra, and a cornercorner with one AlNO4 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 66–68°. The Al–N bond length is 1.80 Å. There are a spread of Al–O bond distances ranging from 1.78–1.86 Å. There are five inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to one N3- and three O2- atoms to form SiNO3 tetrahedra that share a cornercorner with one AlO4 tetrahedra and a cornercorner with one SiN2O2 tetrahedra. The Si–N bond length is 1.69 Å. There is one shorter (1.64 Å) and two longer (1.67 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two AlO4 tetrahedra and a cornercorner with one AlNO4 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two AlO4 tetrahedra and a cornercorner with one AlNO4 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the fourth Si4+ site, Si4+ is bonded to one N3- and three O2- atoms to form SiNO3 tetrahedra that share a cornercorner with one AlO4 tetrahedra and a cornercorner with one SiN2O2 tetrahedra. The Si–N bond length is 1.68 Å. There are a spread of Si–O bond distances ranging from 1.64–1.68 Å. In the fifth Si4+ site, Si4+ is bonded to two N3- and two O2- atoms to form SiN2O2 tetrahedra that share corners with two AlNO5 octahedra and corners with two SiNO3 tetrahedra. The corner-sharing octahedra tilt angles range from 56–57°. There is one shorter (1.73 Å) and one longer (1.74 Å) Si–N bond length. Both Si–O bond lengths are 1.68 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded in a 2-coordinate geometry to two Nd3+ and two Si4+ atoms. In the second N3- site, N3- is bonded in a 2-coordinate geometry to two Nd3+ and two Si4+ atoms. In the third N3- site, N3- is bonded in a 4-coordinate geometry to one Nd3+ and three Al3+ atoms. There are twenty-five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Al3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Nd3+ and two Al3+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+ and two Al3+ atoms. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to three Nd3+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to three Nd3+ and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Al3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Al3+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Al3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+, one Al3+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+ and two Al3+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Nd3+ and two Al3+ atoms. In the fourteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Al3+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Nd3+, one Al3+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+ and two Al3+ atoms. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+ and two Al3+ atoms. In the eighteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+, one Al3+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+ and two Al3+ atoms. In the twentieth O2- site, O2- is bonded in a distorted single-bond geometry to three Nd3+ and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a distorted single-bond geometry to three Nd3+ and one Si4+ atom. In the twenty-second O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Al3+, and one Si4+ atom. In the twenty-third O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Al3+, and one Si4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Al3+, and one Si4+ atom. In the twenty-fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+ and two Al3+ atoms.

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2020-04-30. Materials Data on Nd6Al7Si5N3O25 by Materials Project. https://doi.org/10.17188/1207958

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