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DOE OSTI · 1698674

Materials Data on Sc4Ti3O12 by Materials Project

Abstract

Sc4Ti3O12 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Sc3+ sites. In the first Sc3+ site, Sc3+ is bonded to seven O2- atoms to form distorted ScO7 pentagonal bipyramids that share a cornercorner with one TiO6 octahedra and an edgeedge with one TiO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Sc–O bond distances ranging from 2.09–2.33 Å. In the second Sc3+ site, Sc3+ is bonded in a 7-coordinate geometry to six O2- atoms. There are a spread of Sc–O bond distances ranging from 2.04–2.19 Å. In the third Sc3+ site, Sc3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sc–O bond distances ranging from 2.05–2.66 Å. In the fourth Sc3+ site, Sc3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sc–O bond distances ranging from 2.05–2.44 Å. There are three inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share a cornercorner with one ScO7 pentagonal bipyramid and an edgeedge with one ScO7 pentagonal bipyramid. There are a spread of Ti–O bond distances ranging from 1.89–2.12 Å. In the second Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.93–2.13 Å. In the third Ti4+ site, Ti4+ is bonded in a 7-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.92–2.11 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to three Ti4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Sc3+ and two Ti4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Sc3+ and two Ti4+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Sc3+ and one Ti4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Sc3+ and one Ti4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Sc3+ and one Ti4+ atom. In the seventh O2- site, O2- is bonded to three Sc3+ and one Ti4+ atom to form OSc3Ti tetrahedra that share corners with five OSc2Ti2 tetrahedra, a cornercorner with one OSc2Ti2 trigonal pyramid, edges with two OSc3Ti tetrahedra, and an edgeedge with one OSc2Ti2 trigonal pyramid. In the eighth O2- site, O2- is bonded to two Sc3+ and two Ti4+ atoms to form OSc2Ti2 tetrahedra that share corners with five OSc3Ti tetrahedra, a cornercorner with one OSc2Ti2 trigonal pyramid, edges with two OSc3Ti tetrahedra, and an edgeedge with one OSc2Ti2 trigonal pyramid. In the ninth O2- site, O2- is bonded to three Sc3+ and one Ti4+ atom to form OSc3Ti tetrahedra that share corners with six OSc3Ti tetrahedra, edges with two OSc3Ti tetrahedra, and an edgeedge with one OSc2Ti2 trigonal pyramid. In the tenth O2- site, O2- is bonded to three Sc3+ and one Ti4+ atom to form distorted OSc3Ti tetrahedra that share corners with four OSc2Ti2 tetrahedra, corners with two equivalent OSc2Ti2 trigonal pyramids, and edges with three OSc3Ti tetrahedra. In the eleventh O2- site, O2- is bonded to three Sc3+ and one Ti4+ atom to form distorted OSc3Ti tetrahedra that share corners with four OSc3Ti tetrahedra, corners with two equivalent OSc2Ti2 trigonal pyramids, and edges with three OSc3Ti tetrahedra. In the twelfth O2- site, O2- is bonded to two Sc3+ and two Ti4+ atoms to form a mixture of distorted edge and corner-sharing OSc2Ti2 trigonal pyramids.

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2020-05-02. Materials Data on Sc4Ti3O12 by Materials Project. https://doi.org/10.17188/1698674

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