Materials Data on Rb2Ta2Si2O11 by Materials Project

Abstract

Rb2Ta2Si2O11 crystallizes in the tetragonal P4_122 space group. The structure is three-dimensional. there are three inequivalent Rb sites. In the first Rb site, Rb is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Rb–O bond distances ranging from 3.02–3.50 Å. In the second Rb site, Rb is bonded in a 1-coordinate geometry to three O atoms. There are a spread of Rb–O bond distances ranging from 2.76–3.18 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 2.99–3.47 Å. There are two inequivalent Ta sites. In the first Ta site, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with four TaO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–44°. There are a spread of Ta–O bond distances ranging from 1.94–2.05 Å. In the second Ta site, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with four TaO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–44°. There are a spread of Ta–O bond distances ranging from 1.93–2.08 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 TaO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–43°. 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 TaO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–43°. There is three shorter (1.63 Å) and one longer (1.65 Å) Si–O bond length. There are twelve inequivalent O sites. In the first O site, O is bonded in a distorted bent 150 degrees 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 Ta and one Si atom. In the third O site, O is bonded in a distorted bent 150 degrees geometry to one Rb and two equivalent Ta atoms. In the fourth O site, O is bonded in a distorted linear geometry to one Rb and two Si atoms. In the fifth O site, O is bonded in a distorted see-saw-like geometry to three Rb and one O atom. The O–O bond length is 1.24 Å. In the sixth O site, O is bonded in a 2-coordinate geometry to one Rb and two Ta atoms. In the seventh O site, O is bonded in a 2-coordinate geometry to one Rb, one Ta, and one Si atom. In the eighth O site, O is bonded in a 2-coordinate geometry to one Rb, one Ta, and one Si atom. In the ninth O site, O is bonded in a distorted bent 150 degrees geometry to one Ta and one Si atom. In the tenth O site, O is bonded in a distorted bent 150 degrees geometry to one Rb and two Ta atoms. In the eleventh O site, O is bonded in a bent 150 degrees geometry to one Rb and two equivalent Ta atoms. In the twelfth O site, O is bonded in a 2-coordinate geometry to one Rb and two Ta atoms.