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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Sr2LaTa3O11 by Materials Project

Sr2LaTa3O11 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Sr2+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. There are four shorter (2.51 Å) and two longer (2.59 Å) Sr–O bond lengths. La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with two equivalent LaO12 cuboctahedra, faces with two equivalent LaO12 cuboctahedra, and faces with eight TaO6 octahedra. There are a spread of La–O bond distances ranging from 2.62–2.88 Å. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with four TaO6 octahedra and faces with two equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 10–19°. There are a spread of Ta–O bond distances ranging from 1.89–2.14 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and faces with four equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–10°. There is two shorter (1.99 Å) and four longer (2.00 Å) Ta–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and two Ta5+ atoms. In the second O2- site, O2- is bonded to three equivalent Sr2+ and one Ta5+ atom to form a mixture of distorted edge and corner-sharing OSr3Ta tetrahedra. In the third O2- site, O2- is bonded in a distorted linear geometry to two equivalent La3+ and two equivalent Ta5+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two equivalent Ta5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr2LaTaO6 by Materials Project

Sr2LaTaO6 is (Cubic) Perovskite-derived structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Sr2+ is bonded to twelve equivalent O2- atoms to form SrO12 cuboctahedra that share corners with twelve equivalent SrO12 cuboctahedra, faces with six equivalent SrO12 cuboctahedra, faces with four equivalent LaO6 octahedra, and faces with four equivalent TaO6 octahedra. All Sr–O bond lengths are 3.06 Å. La3+ is bonded to six equivalent O2- atoms to form LaO6 octahedra that share corners with six equivalent TaO6 octahedra and faces with eight equivalent SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All La–O bond lengths are 2.33 Å. Ta5+ is bonded to six equivalent O2- atoms to form TaO6 octahedra that share corners with six equivalent LaO6 octahedra and faces with eight equivalent SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–O bond lengths are 2.00 Å. O2- is bonded in a distorted linear geometry to four equivalent Sr2+, one La3+, and one Ta5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3LaTa3O12 by Materials Project

Sr3LaTa3O12 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of Sr–O bond distances ranging from 2.57–3.14 Å. In the second Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with six equivalent SrO12 cuboctahedra, faces with three equivalent SrO12 cuboctahedra, and faces with seven TaO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.65–2.91 Å. In the third Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with six equivalent SrO12 cuboctahedra, faces with three equivalent SrO12 cuboctahedra, and faces with seven TaO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.62–2.94 Å. La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are three shorter (2.42 Å) and six longer (2.90 Å) La–O bond lengths. There are three inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with three equivalent TaO6 octahedra and faces with four SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. There are three shorter (1.90 Å) and three longer (2.13 Å) Ta–O bond lengths. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with three equivalent TaO6 octahedra and faces with four SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. There are three shorter (1.92 Å) and three longer (2.10 Å) Ta–O bond lengths. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and faces with six SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. There are three shorter (1.99 Å) and three longer (2.01 Å) Ta–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to three Sr2+ and two Ta5+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two Ta5+ atoms. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+, two equivalent La3+, and one Ta5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Sr2+, one La3+, and one Ta5+ atom.

36 MATERIALS SCIENCE↗