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DOE OSTI · 1701186

Materials Data on Sr4Ga2O7 by Materials Project

Abstract

Sr4Ga2O7 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are thirty-two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.98 Å. In the second Sr2+ site, Sr2+ is bonded in a 4-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–3.15 Å. In the third Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six GaO4 tetrahedra and an edgeedge with one SrO6 pentagonal pyramid. There are a spread of Sr–O bond distances ranging from 2.40–2.55 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.50–2.96 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.55–3.06 Å. In the sixth Sr2+ site, Sr2+ is bonded to seven O2- atoms to form distorted SrO7 pentagonal bipyramids that share corners with two GaO4 tetrahedra, edges with two SrO6 octahedra, and edges with three GaO4 tetrahedra. There are a spread of Sr–O bond distances ranging from 2.51–2.82 Å. In the seventh Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.80 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.38–3.19 Å. In the ninth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.47–2.85 Å. In the tenth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 octahedra that share corners with six GaO4 tetrahedra. There are a spread of Sr–O bond distances ranging from 2.39–2.59 Å. In the eleventh Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.37–2.70 Å. In the twelfth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.48–3.16 Å. In the thirteenth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.56–3.10 Å. In the fourteenth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 octahedra that share a cornercorner with one SrO6 pentagonal pyramid and corners with six GaO4 tetrahedra. There are a spread of Sr–O bond distances ranging from 2.35–2.96 Å. In the fifteenth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.38–3.16 Å. In the sixteenth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 octahedra that share corners with six GaO4 tetrahedra and an edgeedge with one SrO7 pentagonal bipyramid. There are a spread of Sr–O bond distances ranging from 2.46–2.65 Å. In the seventeenth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.47–2.87 Å. In the eighteenth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.49–2.87 Å. In the nineteenth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.45–3.02 Å. In the twentieth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 pentagonal pyramids that share corners with two SrO6 octahedra, corners with four GaO4 tetrahedra, and an edgeedge with one GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 25–29°. There are a spread of Sr–O bond distances ranging from 2.39–2.95 Å. In the twenty-first Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 pentagonal pyramids that share corners with five GaO4 tetrahedra, an edgeedge with one SrO6 octahedra, an edgeedge with one GaO4 tetrahedra, and a faceface with one SrO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.44–2.71 Å. In the twenty-second Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.50–3.12 Å. In the twenty-third Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.42–2.88 Å. In the twenty-fourth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 octahedra that share corners with six GaO4 tetrahedra and a faceface with one SrO6 pentagonal pyramid. There are a spread of Sr–O bond distances ranging from 2.43–2.56 Å. In the twenty-fifth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–3.01 Å. In the twenty-sixth Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.48–3.19 Å. In the twenty-seventh Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.47–3.13 Å. In the twenty-eighth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.42–2.66 Å. In the twenty-ninth Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.52–3.10 Å. In the thirtieth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.41–2.99 Å. In the thirty-first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.40–3.05 Å. In the thirty-second Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 octahedra that share a cornercorner with one SrO6 pentagonal pyramid, corners with six GaO4 tetrahedra, and an edgeedge with one SrO7 pentagonal bipyramid. There are a spread of Sr–O bond distances ranging from 2.40–2.64 Å. There are sixteen inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with two SrO6 octahedra and a cornercorner with one GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–61°. There are a spread of Ga–O bond distances ranging from 1.83–1.95 Å. In the second Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three SrO6 octahedra, a cornercorner with one SrO6 pentagonal pyramid, and a cornercorner with one GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 14–62°. There are a spread of Ga–O bond distances ranging from 1.81–1.95 Å. In the third Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share a cornercorner with one SrO6 octahedra and corners with two GaO4 tetrahedra. The corner-sharing octahedral tilt angles are 29°. There are a spread of Ga–O bond distances ranging from 1.82–1.92 Å. In the fourth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with two SrO6 octahedra, corners with two SrO6 pentagonal pyramids, and a cornercorner with one GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–59°. There are a spread of Ga–O bond distances ranging from 1.85–1.94 Å. In the fifth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three SrO6 octahedra, a cornercorner with one SrO6 pentagonal pyramid, a cornercorner with one GaO4 tetrahedra, and an edgeedge with one SrO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 18–49°. There are a spread of Ga–O bond distances ranging from 1.83–1.90 Å. In the sixth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three SrO6 octahedra, a cornercorner with one SrO7 pentagonal bipyramid, and an edgeedge with one SrO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 57–79°. There are a spread of Ga–O bond distances ranging from 1.88–1.90 Å. In the seventh Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three SrO6 octahedra and a cornercorner with one GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–59°. There are a spread of Ga–O bond distances ranging from 1.83–1.90 Å. In the eighth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share a cornercorner with one SrO6 octahedra and corners with two GaO4 tetrahedra. The corner-sharing octahedral tilt angles are 20°. There are a spread of Ga–O bond distances ranging from 1.83–1.90 Å. In the ninth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three SrO6 octahedra and a cornercorner with one SrO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 19–77°. There is two shorter (1.89 Å) and two longer (1.90 Å) Ga–O bond length. In the tenth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three SrO6 octahedra, a cornercorner with one SrO7 pentagonal bipyramid, and a cornercorner with one SrO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 16–58°. There are a spread of Ga–O bond distances ranging from 1.86–1.91 Å. In the eleventh Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share a cornercorner with one SrO6 octahedra, corners with two GaO4 tetrahedra, and an edgeedge with one SrO6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 26°. There are a spread of Ga–O bond distances ranging from 1.81–1.93 Å. In the twelfth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with two SrO6 octahedra, a cornercorner with one GaO4 tetrahedra, and an edgeedge with one SrO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 32–43°. There are a spread of Ga–O bond distances ranging from 1.82–1.91 Å. In the thirteenth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with two SrO6 octahedra, corners with two SrO6 pentagonal pyramids, and a cornercorner with one GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–53°. There are a spread of Ga–O bond distances ranging from 1.84–1.92 Å. In the fourteenth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share a cornercorner with one SrO6 octahedra, a cornercorner with one SrO6 pentagonal pyramid, corners with two GaO4 tetrahedra, and an edgeedge with one SrO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 37°. There are a spread of Ga–O bond distances ranging from 1.81–1.89 Å. In the fifteenth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three SrO6 octahedra. The corner-sharing octahedra tilt angles range from 1–48°. There are a spread of Ga–O bond distances ranging from 1.86–1.95 Å. In the sixteenth Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three SrO6 octahedra and a cornercorner with one GaO4 tetrahedra. The corner-sharing octahedra tilt angles range from 17–42°. There are a spread of Ga–O bond distances ranging from 1.83–1.90 Å. There are fifty-six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to five Sr2+ and one Ga3+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Ga3+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Ga3+ atom. In the fourth O2- site, O2- is bonded in a 2-coor

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2019-01-12. Materials Data on Sr4Ga2O7 by Materials Project. https://doi.org/10.17188/1701186

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