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DOE OSTI · 1758780

Materials Data on Rb2Nb2Si2O11 by Materials Project

Abstract

Rb2Nb2Si2O11 crystallizes in the tetragonal P4_322 space group. The structure is three-dimensional. there are three inequivalent Rb sites. In the first Rb site, Rb is bonded in a 2-coordinate geometry to four O atoms. There are a spread of Rb–O bond distances ranging from 2.80–3.13 Å. In the second Rb site, Rb is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Rb–O bond distances ranging from 3.02–3.32 Å. In the third Rb site, Rb is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of Rb–O bond distances ranging from 2.99–3.56 Å. There are two inequivalent Nb sites. In the first Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with four NbO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–44°. There are a spread of Nb–O bond distances ranging from 1.89–2.09 Å. In the second Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with four NbO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–44°. There are a spread of Nb–O bond distances ranging from 1.88–2.10 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two NbO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–45°. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two NbO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–45°. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. There are twelve inequivalent O sites. In the first O site, O is bonded in a distorted linear geometry to one Rb and two Si atoms. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one Rb and two Nb atoms. In the third O site, O is bonded in a 4-coordinate geometry to three Rb and one O atom. The O–O bond length is 1.24 Å. In the fourth O site, O is bonded in a distorted bent 150 degrees geometry to one Rb and two Si atoms. In the fifth O site, O is bonded in a 2-coordinate geometry to one Rb and two Nb atoms. In the sixth O site, O is bonded in a 2-coordinate geometry to one Rb, one Nb, and one Si atom. In the seventh O site, O is bonded in a 2-coordinate geometry to two Rb, one Nb, and one Si atom. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to one Rb and two equivalent Nb atoms. In the ninth O site, O is bonded in a 2-coordinate geometry to one Rb and two Nb atoms. In the tenth O site, O is bonded in a distorted bent 150 degrees geometry to one Nb and one Si atom. In the eleventh O site, O is bonded in a distorted bent 150 degrees geometry to one Nb and one Si atom. In the twelfth O site, O is bonded in a bent 150 degrees geometry to two equivalent Nb atoms.

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2020-09-03. Materials Data on Rb2Nb2Si2O11 by Materials Project. https://doi.org/10.17188/1758780

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