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DOE OSTI · 1707923

Materials Data on Sr2CaNbO6 by Materials Project

Abstract

Sr2CaNbO6 crystallizes in the tetragonal P-4 space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a distorted body-centered cubic geometry to eight O atoms. There are a spread of Sr–O bond distances ranging from 2.58–2.93 Å. In the second Sr site, Sr is bonded in a distorted body-centered cubic geometry to eight O atoms. There are a spread of Sr–O bond distances ranging from 2.58–2.94 Å. There are three inequivalent Ca sites. In the first Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–34°. There are three shorter (2.30 Å) and three longer (2.31 Å) Ca–O bond lengths. In the second Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–35°. There are two shorter (2.30 Å) and four longer (2.32 Å) Ca–O bond lengths. In the third Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–35°. There are two shorter (2.29 Å) and four longer (2.32 Å) Ca–O bond lengths. There are three inequivalent Nb sites. In the first Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with six CaO6 octahedra. The corner-sharing octahedra tilt angles range from 0–34°. There are four shorter (2.01 Å) and two longer (2.03 Å) Nb–O bond lengths. In the second Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with six CaO6 octahedra. The corner-sharing octahedra tilt angles range from 0–33°. All Nb–O bond lengths are 2.02 Å. In the third Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with six CaO6 octahedra. The corner-sharing octahedra tilt angles range from 0–35°. There are a spread of Nb–O bond distances ranging from 2.01–2.03 Å. There are eight inequivalent O sites. In the first O site, O is bonded to four Sr, one Ca, and one Nb atom to form distorted OSr4CaNb octahedra that share corners with six OSr4CaNb octahedra, corners with eight OSr2CaNb tetrahedra, edges with four OSr4CaNb octahedra, and edges with eight OSr2CaNb tetrahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the second O site, O is bonded to four Sr, one Ca, and one Nb atom to form distorted OSr4CaNb octahedra that share corners with six equivalent OSr4CaNb octahedra, corners with eight OSr2CaNb tetrahedra, edges with four OSr4CaNb octahedra, and edges with eight OSr2CaNb tetrahedra. The corner-sharing octahedra tilt angles range from 0–6°. In the third O site, O is bonded to two Sr, one Ca, and one Nb atom to form distorted OSr2CaNb tetrahedra that share corners with four OSr4CaNb octahedra, corners with ten OSr2CaNb tetrahedra, edges with four OSr4CaNb octahedra, and an edgeedge with one OSr2CaNb tetrahedra. The corner-sharing octahedra tilt angles range from 67–68°. In the fourth O site, O is bonded to two Sr, one Ca, and one Nb atom to form distorted OSr2CaNb tetrahedra that share corners with four OSr4CaNb octahedra, corners with ten OSr2CaNb tetrahedra, edges with four OSr4CaNb octahedra, and an edgeedge with one OSr2CaNb tetrahedra. The corner-sharing octahedra tilt angles range from 67–68°. In the fifth O site, O is bonded to four Sr, one Ca, and one Nb atom to form distorted OSr4CaNb octahedra that share corners with six equivalent OSr4CaNb octahedra, corners with eight OSr2CaNb tetrahedra, edges with four OSr4CaNb octahedra, and edges with eight OSr2CaNb tetrahedra. The corner-sharing octahedra tilt angles range from 0–6°. In the sixth O site, O is bonded to four Sr, one Ca, and one Nb atom to form distorted OSr4CaNb octahedra that share corners with six OSr4CaNb octahedra, corners with eight OSr2CaNb tetrahedra, edges with four OSr4CaNb octahedra, and edges with eight OSr2CaNb tetrahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the seventh O site, O is bonded to two Sr, one Ca, and one Nb atom to form distorted OSr2CaNb tetrahedra that share corners with four OSr4CaNb octahedra, corners with ten OSr2CaNb tetrahedra, edges with four OSr4CaNb octahedra, and an edgeedge with one OSr2CaNb tetrahedra. The corner-sharing octahedra tilt angles range from 66–67°. In the eighth O site, O is bonded to two Sr, one Ca, and one Nb atom to form distorted OSr2CaNb tetrahedra that share corners with four OSr4CaNb octahedra, corners with ten OSr2CaNb tetrahedra, edges with four OSr4CaNb octahedra, and an edgeedge with one OSr2CaNb tetrahedra. The corner-sharing octahedra tilt angles range from 66–67°.

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2019-01-12. Materials Data on Sr2CaNbO6 by Materials Project. https://doi.org/10.17188/1707923

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