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DOE OSTI · 1289202

Materials Data on Dy2(BiO2)7 by Materials Project

Abstract

Dy2(BiO2)7 crystallizes in the monoclinic Cm space group. The structure is two-dimensional and consists of one Dy2(BiO2)7 sheet oriented in the (0, 0, 1) direction. there are two inequivalent Dy3+ sites. In the first Dy3+ site, Dy3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Dy–O bond distances ranging from 2.38–2.62 Å. In the second Dy3+ site, Dy3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Dy–O bond distances ranging from 2.28–2.57 Å. There are seven inequivalent Bi+3.14+ sites. In the first Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form a mixture of distorted edge and corner-sharing BiO5 square pyramids. There are one shorter (2.13 Å) and four longer (2.41 Å) Bi–O bond lengths. In the second Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form distorted corner-sharing BiO5 trigonal bipyramids. There are a spread of Bi–O bond distances ranging from 2.18–2.56 Å. In the third Bi+3.14+ site, Bi+3.14+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Bi–O bond distances ranging from 2.19–2.23 Å. In the fourth Bi+3.14+ site, Bi+3.14+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Bi–O bond distances ranging from 2.17–2.24 Å. In the fifth Bi+3.14+ site, Bi+3.14+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.30–2.67 Å. In the sixth Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form distorted corner-sharing BiO5 trigonal bipyramids. There are a spread of Bi–O bond distances ranging from 2.15–2.53 Å. In the seventh Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form a mixture of distorted edge and corner-sharing BiO5 square pyramids. There are a spread of Bi–O bond distances ranging from 2.12–2.45 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to three Dy3+ and one Bi+3.14+ atom to form a mixture of edge and corner-sharing ODy3Bi tetrahedra. In the second O2- site, O2- is bonded in a trigonal planar geometry to three Bi+3.14+ atoms. In the third O2- site, O2- is bonded to one Dy3+ and three Bi+3.14+ atoms to form a mixture of distorted edge and corner-sharing ODyBi3 tetrahedra. In the fourth O2- site, O2- is bonded to two equivalent Dy3+ and two Bi+3.14+ atoms to form a mixture of edge and corner-sharing ODy2Bi2 tetrahedra. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Bi+3.14+ atoms. In the sixth O2- site, O2- is bonded to one Dy3+ and three Bi+3.14+ atoms to form a mixture of distorted edge and corner-sharing ODyBi3 tetrahedra. In the seventh O2- site, O2- is bonded to three Dy3+ and one Bi+3.14+ atom to form ODy3Bi tetrahedra that share corners with ten ODy2Bi2 tetrahedra and edges with six ODy3Bi tetrahedra. In the eighth O2- site, O2- is bonded to one Dy3+ and three Bi+3.14+ atoms to form ODyBi3 tetrahedra that share corners with ten ODy3Bi tetrahedra and edges with six OBi4 tetrahedra. In the ninth O2- site, O2- is bonded to four Bi+3.14+ atoms to form distorted OBi4 tetrahedra that share corners with seven OBi4 tetrahedra and edges with three ODyBi3 tetrahedra. In the tenth O2- site, O2- is bonded to one Dy3+ and three Bi+3.14+ atoms to form distorted ODyBi3 tetrahedra that share corners with eleven ODy3Bi tetrahedra and edges with four ODyBi3 tetrahedra. In the eleventh O2- site, O2- is bonded to one Dy3+ and three Bi+3.14+ atoms to form a mixture of distorted edge and corner-sharing ODyBi3 tetrahedra. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Bi+3.14+ atoms. In the thirteenth O2- site, O2- is bonded in a trigonal planar geometry to three Bi+3.14+ atoms. In the fourteenth O2- site, O2- is bonded to two equivalent Dy3+ and two Bi+3.14+ atoms to form distorted ODy2Bi2 tetrahedra that share corners with twelve ODy3Bi tetrahedra and edges with five ODyBi3 tetrahedra.

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2020-04-29. Materials Data on Dy2(BiO2)7 by Materials Project. https://doi.org/10.17188/1289202

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