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DOE OSTI2020

Materials Data on Sr4CaCr5O15 by Materials Project

Sr4CaCr5O15 is (Cubic) Perovskite-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with three equivalent SrO12 cuboctahedra, faces with three equivalent CaO12 cuboctahedra, and faces with eight CrO6 octahedra. There are three shorter (2.73 Å) and nine longer (2.74 Å) Sr–O bond lengths. In the second Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with three equivalent CaO12 cuboctahedra, corners with nine SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, and faces with eight CrO6 octahedra. There are nine shorter (2.74 Å) and three longer (2.75 Å) Sr–O bond lengths. Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with six equivalent SrO12 cuboctahedra, corners with six equivalent CaO12 cuboctahedra, faces with six equivalent SrO12 cuboctahedra, and faces with eight CrO6 octahedra. There are six shorter (2.72 Å) and six longer (2.74 Å) Ca–O bond lengths. There are three inequivalent Cr4+ sites. In the first Cr4+ site, Cr4+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six CrO6 octahedra, faces with three equivalent CaO12 cuboctahedra, and faces with five SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There is three shorter (1.93 Å) and three longer (1.96 Å) Cr–O bond length. In the second Cr4+ site, Cr4+ is bonded to six equivalent O2- atoms to form CrO6 octahedra that share corners with six equivalent CrO6 octahedra and faces with eight SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Cr–O bond lengths are 1.96 Å. In the third Cr4+ site, Cr4+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six CrO6 octahedra, a faceface with one CaO12 cuboctahedra, and faces with seven SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There is three shorter (1.91 Å) and three longer (1.92 Å) Cr–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sr2+, two equivalent Ca2+, and two equivalent Cr4+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to three Sr2+, one Ca2+, and two Cr4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two Cr4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrCaCr2O6 by Materials Project

SrCaCr2O6 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, corners with eight equivalent CaO12 cuboctahedra, faces with two equivalent SrO12 cuboctahedra, faces with four equivalent CaO12 cuboctahedra, and faces with eight equivalent CrO6 octahedra. There are eight shorter (2.74 Å) and four longer (2.75 Å) Sr–O bond lengths. Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with four equivalent CaO12 cuboctahedra, corners with eight equivalent SrO12 cuboctahedra, faces with two equivalent CaO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight equivalent CrO6 octahedra. There are eight shorter (2.69 Å) and four longer (2.75 Å) Ca–O bond lengths. Cr4+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six equivalent CrO6 octahedra, faces with four equivalent SrO12 cuboctahedra, and faces with four equivalent CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There is two shorter (1.90 Å) and four longer (1.94 Å) Cr–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sr2+, two equivalent Ca2+, and two equivalent Cr4+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sr2+, two equivalent Ca2+, and two equivalent Cr4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrCaCr2O6 by Materials Project

SrCaCr2O6 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, corners with eight equivalent CaO12 cuboctahedra, faces with two equivalent CaO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight equivalent CrO6 octahedra. There are four shorter (2.70 Å) and eight longer (2.77 Å) Sr–O bond lengths. Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with four equivalent CaO12 cuboctahedra, corners with eight equivalent SrO12 cuboctahedra, faces with two equivalent SrO12 cuboctahedra, faces with four equivalent CaO12 cuboctahedra, and faces with eight equivalent CrO6 octahedra. There are four shorter (2.70 Å) and eight longer (2.71 Å) Ca–O bond lengths. Cr4+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six equivalent CrO6 octahedra, faces with four equivalent SrO12 cuboctahedra, and faces with four equivalent CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Cr–O bond distances ranging from 1.91–1.99 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Sr2+ and two equivalent Cr4+ atoms to form a mixture of distorted edge and corner-sharing OSr4Cr2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ca2+ and two equivalent Cr4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sr2+, two equivalent Ca2+, and two equivalent Cr4+ atoms.

36 MATERIALS SCIENCE↗