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DOE OSTI · 1321322

Materials Data on Ca(AgO2)2 by Materials Project

Abstract

Ca(AgO2)2 is Spinel-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to four O2- atoms to form CaO4 tetrahedra that share corners with three CaO6 octahedra and corners with nine AgO6 octahedra. The corner-sharing octahedra tilt angles range from 57–63°. There are a spread of Ca–O bond distances ranging from 2.24–2.34 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six AgO4 tetrahedra, edges with two CaO6 octahedra, and edges with four AgO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.30–2.42 Å. In the third Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with two equivalent CaO4 tetrahedra, corners with four AgO4 tetrahedra, an edgeedge with one CaO6 octahedra, and edges with five AgO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.30–2.39 Å. In the fourth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six AgO4 tetrahedra, edges with two CaO6 octahedra, and edges with four AgO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.30–2.38 Å. In the fifth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six AgO4 tetrahedra, edges with two CaO6 octahedra, and edges with four equivalent AgO6 octahedra. There are four shorter (2.30 Å) and two longer (2.36 Å) Ca–O bond lengths. In the sixth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share a cornercorner with one CaO4 tetrahedra, corners with five AgO4 tetrahedra, an edgeedge with one CaO6 octahedra, and edges with five AgO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.31–2.36 Å. There are nine inequivalent Ag3+ sites. In the first Ag3+ site, Ag3+ is bonded to six O2- atoms to form AgO6 octahedra that share corners with two equivalent CaO4 tetrahedra, corners with four AgO4 tetrahedra, edges with three CaO6 octahedra, and edges with three AgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.05–2.22 Å. In the second Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with six CaO6 octahedra and corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 55–63°. There are a spread of Ag–O bond distances ranging from 2.19–2.28 Å. In the third Ag3+ site, Ag3+ is bonded to six O2- atoms to form AgO6 octahedra that share corners with three equivalent CaO4 tetrahedra, corners with three equivalent AgO4 tetrahedra, edges with two CaO6 octahedra, and edges with four AgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.10–2.27 Å. In the fourth Ag3+ site, Ag3+ is bonded to six O2- atoms to form AgO6 octahedra that share corners with six AgO4 tetrahedra, edges with two equivalent AgO6 octahedra, and edges with four CaO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.06–2.19 Å. In the fifth Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with six CaO6 octahedra and corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 53–64°. There are one shorter (2.17 Å) and three longer (2.20 Å) Ag–O bond lengths. In the sixth Ag3+ site, Ag3+ is bonded to six O2- atoms to form AgO6 octahedra that share a cornercorner with one CaO4 tetrahedra, corners with five AgO4 tetrahedra, edges with three CaO6 octahedra, and edges with three AgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.05–2.28 Å. In the seventh Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with six CaO6 octahedra and corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 52–65°. There are a spread of Ag–O bond distances ranging from 2.19–2.21 Å. In the eighth Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with six CaO6 octahedra and corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 55–64°. There are a spread of Ag–O bond distances ranging from 2.18–2.33 Å. In the ninth Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with three CaO6 octahedra and corners with nine AgO6 octahedra. The corner-sharing octahedra tilt angles range from 55–68°. There are a spread of Ag–O bond distances ranging from 2.15–2.27 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded to two Ca2+ and two Ag3+ atoms to form distorted OCa2Ag2 tetrahedra that share corners with two OCa2Ag2 tetrahedra, corners with five OCaAg3 trigonal pyramids, an edgeedge with one OCa2Ag2 tetrahedra, and an edgeedge with one OCaAg3 trigonal pyramid. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three Ag3+ atoms. In the third O2- site, O2- is bonded to one Ca2+ and three Ag3+ atoms to form distorted OCaAg3 trigonal pyramids that share corners with three OCa2Ag2 tetrahedra, corners with four OCaAg3 trigonal pyramids, and edges with two equivalent OCa2Ag2 tetrahedra. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Ca2+ and two Ag3+ atoms. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three Ag3+ atoms. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three Ag3+ atoms. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two Ag3+ atoms. In the eighth O2- site, O2- is bonded to one Ca2+ and three Ag3+ atoms to form distorted OCaAg3 trigonal pyramids that share corners with four equivalent OCa2Ag2 tetrahedra and corners with four OCaAg3 trigonal pyramids. In the ninth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three Ag3+ atoms. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two Ag3+ atoms. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three Ag3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Ca2+ and two Ag3+ atoms. In the thirteenth O2- site, O2- is bonded to two Ca2+ and two equivalent Ag3+ atoms to form distorted OCa2Ag2 tetrahedra that share corners with two equivalent OCa2Ag2 tetrahedra and corners with eight OCaAg3 trigonal pyramids. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three Ag3+ atoms. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three Ag3+ atoms. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Ag3+ atoms. In the seventeenth O2- site, O2- is bonded to one Ca2+ and three Ag3+ atoms to form distorted OCaAg3 trigonal pyramids that share corners with four OCa2Ag2 tetrahedra, corners with three OCaAg3 trigonal pyramids, and edges with two OCaAg3 trigonal pyramids. In the eighteenth O2- site, O2- is bonded to one Ca2+ and three Ag3+ atoms to form distorted OCaAg3 trigonal pyramids that share corners with three equivalent OCa2Ag2 tetrahedra and edges with two equivalent OCaAg3 trigonal pyramids.

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2020-04-29. Materials Data on Ca(AgO2)2 by Materials Project. https://doi.org/10.17188/1321322

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