DOE OSTI2020
Mg(AgO2)2 is Spinel-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine AgO6 octahedra. The corner-sharing octahedra tilt angles range from 50–62°. There are a spread of Mg–O bond distances ranging from 2.04–2.09 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six AgO4 tetrahedra, edges with two MgO6 octahedra, and edges with four AgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.09–2.15 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four AgO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five AgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.10–2.15 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six AgO4 tetrahedra, edges with two MgO6 octahedra, and edges with four AgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.10–2.14 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six AgO4 tetrahedra, edges with two MgO6 octahedra, and edges with four AgO6 octahedra. There are four shorter (2.09 Å) and two longer (2.13 Å) Mg–O bond lengths. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five AgO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five AgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.15 Å. There are twelve 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 MgO4 tetrahedra, corners with four AgO4 tetrahedra, edges with three MgO6 octahedra, and edges with three AgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.06–2.23 Å. In the second Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with six MgO6 octahedra and corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 57–65°. There are three shorter (2.18 Å) and one longer (2.23 Å) Ag–O bond lengths. In the third Ag3+ site, Ag3+ is bonded to six O2- atoms to form AgO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent AgO4 tetrahedra, edges with two MgO6 octahedra, and edges with four AgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.10–2.25 Å. In the fourth Ag3+ site, Ag3+ is bonded to six O2- atoms to form AgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four AgO4 tetrahedra, edges with three MgO6 octahedra, and edges with three AgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.06–2.24 Å. In the fifth 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 MgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.07–2.15 Å. In the sixth Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with six MgO6 octahedra and corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Ag–O bond distances ranging from 2.16–2.19 Å. In the seventh 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 MgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.07–2.15 Å. In the eighth Ag3+ site, Ag3+ is bonded to six O2- atoms to form AgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five AgO4 tetrahedra, edges with three MgO6 octahedra, and edges with three AgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.06–2.21 Å. In the ninth Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with six MgO6 octahedra and corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 57–64°. There are a spread of Ag–O bond distances ranging from 2.13–2.19 Å. In the tenth Ag3+ site, Ag3+ is bonded to six O2- atoms to form AgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five AgO4 tetrahedra, edges with three MgO6 octahedra, and edges with three AgO6 octahedra. There are a spread of Ag–O bond distances ranging from 2.06–2.20 Å. In the eleventh Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with six MgO6 octahedra and corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Ag–O bond distances ranging from 2.17–2.19 Å. In the twelfth Ag3+ site, Ag3+ is bonded to four O2- atoms to form AgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine AgO6 octahedra. The corner-sharing octahedra tilt angles range from 58–63°. There are a spread of Ag–O bond distances ranging from 2.12–2.21 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Ag3+ atoms. In the second O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 tetrahedra that share corners with six OMg2Ag2 tetrahedra and corners with six OMgAg3 trigonal pyramids. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Ag3+ atoms. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Ag3+ atoms. In the fifth O2- site, O2- is bonded to two Mg2+ and two Ag3+ atoms to form distorted OMg2Ag2 tetrahedra that share corners with seven OMg2Ag2 tetrahedra, corners with five OMgAg3 trigonal pyramids, an edgeedge with one OMg2Ag2 tetrahedra, and edges with two OMgAg3 trigonal pyramids. In the sixth O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 trigonal pyramids that share corners with six OMgAg3 tetrahedra, corners with two OMgAg3 trigonal pyramids, edges with two OMg2Ag2 tetrahedra, and an edgeedge with one OMgAg3 trigonal pyramid. In the seventh O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 trigonal pyramids that share corners with six OMg2Ag2 tetrahedra, corners with six OMgAg3 trigonal pyramids, edges with two OMg2Ag2 tetrahedra, and an edgeedge with one OMgAg3 trigonal pyramid. In the eighth O2- site, O2- is bonded to two Mg2+ and two Ag3+ atoms to form distorted OMg2Ag2 tetrahedra that share corners with five OMgAg3 tetrahedra, corners with three OMgAg3 trigonal pyramids, an edgeedge with one OMg2Ag2 tetrahedra, and edges with two OMgAg3 trigonal pyramids. In the ninth O2- site, O2- is bonded to two Mg2+ and two Ag3+ atoms to form distorted OMg2Ag2 tetrahedra that share corners with seven OMg2Ag2 tetrahedra, corners with five OMgAg3 trigonal pyramids, an edgeedge with one OMg2Ag2 tetrahedra, and edges with two OMgAg3 trigonal pyramids. In the tenth O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 trigonal pyramids that share corners with five OMgAg3 tetrahedra, a cornercorner with one OAg4 trigonal pyramid, edges with two OMg2Ag2 tetrahedra, and an edgeedge with one OMgAg3 trigonal pyramid. In the eleventh O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 trigonal pyramids that share corners with seven OMg2Ag2 tetrahedra, corners with five OMgAg3 trigonal pyramids, edges with two OMg2Ag2 tetrahedra, and an edgeedge with one OMgAg3 trigonal pyramid. In the twelfth O2- site, O2- is bonded to two Mg2+ and two Ag3+ atoms to form distorted OMg2Ag2 tetrahedra that share corners with five OMgAg3 tetrahedra, corners with three OMgAg3 trigonal pyramids, an edgeedge with one OMg2Ag2 tetrahedra, and edges with two OMgAg3 trigonal pyramids. In the thirteenth O2- site, O2- is bonded to two Mg2+ and two Ag3+ atoms to form distorted OMg2Ag2 tetrahedra that share corners with six OMg2Ag2 tetrahedra, corners with six OMgAg3 trigonal pyramids, an edgeedge with one OMg2Ag2 tetrahedra, and an edgeedge with one OMgAg3 trigonal pyramid. In the fourteenth O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 trigonal pyramids that share corners with six OMg2Ag2 tetrahedra, corners with six OMgAg3 trigonal pyramids, edges with two OMg2Ag2 tetrahedra, and an edgeedge with one OMgAg3 trigonal pyramid. In the fifteenth O2- site, O2- is bonded to two Mg2+ and two Ag3+ atoms to form distorted OMg2Ag2 tetrahedra that share corners with six OMg2Ag2 tetrahedra, corners with six OMgAg3 trigonal pyramids, an edgeedge with one OMg2Ag2 tetrahedra, and edges with two OMgAg3 trigonal pyramids. In the sixteenth O2- site, O2- is bonded to two Mg2+ and two Ag3+ atoms to form distorted OMg2Ag2 tetrahedra that share corners with six OMg2Ag2 tetrahedra, corners with six OMgAg3 trigonal pyramids, an edgeedge with one OMg2Ag2 tetrahedra, and an edgeedge with one OMgAg3 trigonal pyramid. In the seventeenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Ag3+ atoms. In the eighteenth O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 trigonal pyramids that share corners with six OMg2Ag2 tetrahedra, corners with six OMgAg3 trigonal pyramids, edges with two OMg2Ag2 tetrahedra, and an edgeedge with one OMgAg3 trigonal pyramid. In the nineteenth O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 trigonal pyramids that share corners with six OMg2Ag2 tetrahedra, corners with six OAg4 trigonal pyramids, and edges with two OMg2Ag2 tetrahedra. In the twentieth O2- site, O2- is bonded to two Mg2+ and two Ag3+ atoms to form distorted OMg2Ag2 tetrahedra that share corners with six OMg2Ag2 tetrahedra, corners with six OMgAg3 trigonal pyramids, an edgeedge with one OMg2Ag2 tetrahedra, and edges with two OMgAg3 trigonal pyramids. In the twenty-first O2- site, O2- is bonded to four Ag3+ atoms to form distorted OAg4 trigonal pyramids that share corners with four OMg2Ag2 tetrahedra, corners with three OMgAg3 trigonal pyramids, edges with two OMgAg3 tetrahedra, and an edgeedge with one OMgAg3 trigonal pyramid. In the twenty-second O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 tetrahedra that share corners with four OMg2Ag2 tetrahedra, corners with three OMgAg3 trigonal pyramids, an edgeedge with one OMgAg3 tetrahedra, and edges with two OMgAg3 trigonal pyramids. In the twenty-third O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 trigonal pyramids that share corners with six OMg2Ag2 tetrahedra, corners with three OMgAg3 trigonal pyramids, edges with two OMgAg3 tetrahedra, and an edgeedge with one OAg4 trigonal pyramid. In the twenty-fourth O2- site, O2- is bonded to one Mg2+ and three Ag3+ atoms to form distorted OMgAg3 tetrahedra that share corners with four OMg2Ag2 tetrahedra, corners with three OMgAg3 trigonal pyramids, an edgeedge with one OMgAg3 tetrahedra, and edges with two OMgAg3 trigonal pyramids.