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DOE OSTI · 1283998

Materials Data on BaYbAl2Si2N5O2 by Materials Project

Abstract

BaYbAl2Si2N5O2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to four N3- and four O2- atoms. There are a spread of Ba–N bond distances ranging from 2.84–3.02 Å. There are a spread of Ba–O bond distances ranging from 2.57–3.28 Å. In the second Ba2+ site, Ba2+ is bonded in a 2-coordinate geometry to one N3- and two O2- atoms. The Ba–N bond length is 2.84 Å. There are one shorter (2.56 Å) and one longer (2.65 Å) Ba–O bond lengths. There are two inequivalent Yb3+ sites. In the first Yb3+ site, Yb3+ is bonded in a 5-coordinate geometry to three N3- and two O2- atoms. There are a spread of Yb–N bond distances ranging from 2.33–2.52 Å. There are one shorter (2.44 Å) and one longer (2.57 Å) Yb–O bond lengths. In the second Yb3+ site, Yb3+ is bonded to three N3- and three O2- atoms to form distorted YbN3O3 pentagonal pyramids that share corners with two AlN2O2 tetrahedra, corners with three SiN4 tetrahedra, and an edgeedge with one AlN2O2 tetrahedra. There are a spread of Yb–N bond distances ranging from 2.57–2.66 Å. There are two shorter (2.40 Å) and one longer (2.43 Å) Yb–O bond lengths. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded in a distorted rectangular see-saw-like geometry to three N3- and one O2- atom. There are a spread of Al–N bond distances ranging from 1.88–2.08 Å. The Al–O bond length is 1.78 Å. In the second Al3+ site, Al3+ is bonded to two N3- and two O2- atoms to form distorted AlN2O2 tetrahedra that share a cornercorner with one YbN3O3 pentagonal pyramid, corners with two SiN4 tetrahedra, and an edgeedge with one YbN3O3 pentagonal pyramid. There is one shorter (1.94 Å) and one longer (1.98 Å) Al–N bond length. There is one shorter (1.78 Å) and one longer (1.88 Å) Al–O bond length. In the third Al3+ site, Al3+ is bonded in a 5-coordinate geometry to three N3- and two O2- atoms. There are a spread of Al–N bond distances ranging from 1.97–2.01 Å. There is one shorter (1.85 Å) and one longer (1.89 Å) Al–O bond length. In the fourth Al3+ site, Al3+ is bonded to three N3- and one O2- atom to form distorted AlN3O tetrahedra that share a cornercorner with one YbN3O3 pentagonal pyramid and corners with two SiN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.91–1.95 Å. The Al–O bond length is 1.76 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded in an L-shaped geometry to two N3- atoms. There is one shorter (1.69 Å) and one longer (1.78 Å) Si–N bond length. In the second Si4+ site, Si4+ is bonded in a distorted T-shaped geometry to three N3- atoms. There are a spread of Si–N bond distances ranging from 1.80–1.93 Å. In the third Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share a cornercorner with one YbN3O3 pentagonal pyramid and corners with two AlN2O2 tetrahedra. There are a spread of Si–N bond distances ranging from 1.69–1.87 Å. In the fourth Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share corners with two equivalent YbN3O3 pentagonal pyramids and corners with two AlN2O2 tetrahedra. There are a spread of Si–N bond distances ranging from 1.73–1.78 Å. There are ten inequivalent N3- sites. In the first N3- site, N3- is bonded in a 3-coordinate geometry to one Ba2+, one Yb3+, one Al3+, and two Si4+ atoms. In the second N3- site, N3- is bonded in a 5-coordinate geometry to one Ba2+, one Yb3+, two Al3+, and one Si4+ atom. In the third N3- site, N3- is bonded in a distorted bent 120 degrees geometry to two Si4+ atoms. In the fourth N3- site, N3- is bonded in a 2-coordinate geometry to one Ba2+ and two Si4+ atoms. In the fifth N3- site, N3- is bonded in a 3-coordinate geometry to one Yb3+, two Al3+, and one Si4+ atom. In the sixth N3- site, N3- is bonded in a 1-coordinate geometry to two Al3+ and two N3- atoms. There is one shorter (1.50 Å) and one longer (1.52 Å) N–N bond length. In the seventh N3- site, N3- is bonded in a 3-coordinate geometry to one Yb3+, two Al3+, and one N3- atom. In the eighth N3- site, N3- is bonded in a 4-coordinate geometry to one Yb3+ and three Si4+ atoms. In the ninth N3- site, N3- is bonded in a 5-coordinate geometry to two Ba2+, one Yb3+, one Al3+, and one Si4+ atom. In the tenth N3- site, N3- is bonded in a 2-coordinate geometry to one Al3+, one Si4+, and one N3- atom. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Ba2+, one Yb3+, and one Al3+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Yb3+, and two Al3+ atoms. In the third O2- site, O2- is bonded in a 5-coordinate geometry to two Ba2+, one Yb3+, and two Al3+ atoms. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+, two Yb3+, and one Al3+ atom.

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2020-05-02. Materials Data on BaYbAl2Si2N5O2 by Materials Project. https://doi.org/10.17188/1283998

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