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DOE OSTI · 1321251

Materials Data on Mg(SnO2)2 by Materials Project

Abstract

Mg(SnO2)2 is Ilmenite-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are eight 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 six SnO6 octahedra. The corner-sharing octahedra tilt angles range from 54–59°. There are a spread of Mg–O bond distances ranging from 2.03–2.74 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra and edges with five SnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.22 Å. In the third Mg2+ site, Mg2+ is bonded in a distorted trigonal non-coplanar geometry to four O2- atoms. There are a spread of Mg–O bond distances ranging from 1.99–2.80 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with three SnO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five SnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.30 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four equivalent SnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.24 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with six SnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four SnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.26–2.32 Å. In the seventh Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with three SnO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with four equivalent SnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.11–2.35 Å. In the eighth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with six SnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four SnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.22–2.32 Å. There are twelve inequivalent Sn3+ sites. In the first Sn3+ site, Sn3+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with two equivalent MgO4 tetrahedra, edges with two equivalent MgO6 octahedra, and edges with three SnO6 octahedra. There are a spread of Sn–O bond distances ranging from 2.06–2.20 Å. In the second Sn3+ site, Sn3+ is bonded to six O2- atoms to form distorted SnO6 octahedra that share edges with two MgO6 octahedra and edges with four SnO6 octahedra. There are a spread of Sn–O bond distances ranging from 2.32–2.70 Å. In the third Sn3+ site, Sn3+ is bonded to four O2- atoms to form SnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six SnO6 octahedra. The corner-sharing octahedra tilt angles range from 56–69°. There are a spread of Sn–O bond distances ranging from 2.19–2.71 Å. In the fourth Sn3+ site, Sn3+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with three SnO4 tetrahedra, edges with three MgO6 octahedra, and edges with three SnO6 octahedra. There are a spread of Sn–O bond distances ranging from 2.06–2.21 Å. In the fifth Sn3+ site, Sn3+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Sn–O bond distances ranging from 2.11–2.79 Å. In the sixth Sn3+ site, Sn3+ is bonded to four O2- atoms to form SnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six SnO6 octahedra. The corner-sharing octahedra tilt angles range from 58–66°. There are a spread of Sn–O bond distances ranging from 2.21–2.67 Å. In the seventh Sn3+ site, Sn3+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with six SnO4 tetrahedra, edges with two equivalent SnO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Sn–O bond distances ranging from 2.08–2.16 Å. In the eighth Sn3+ site, Sn3+ is bonded to four O2- atoms to form SnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six SnO6 octahedra. The corner-sharing octahedra tilt angles range from 55–70°. There are a spread of Sn–O bond distances ranging from 2.20–2.59 Å. In the ninth Sn3+ site, Sn3+ is bonded to six O2- atoms to form SnO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with three SnO4 tetrahedra, edges with two equivalent SnO6 octahedra, and edges with three MgO6 octahedra. There are a spread of Sn–O bond distances ranging from 2.08–2.16 Å. In the tenth Sn3+ site, Sn3+ is bonded to four O2- atoms to form SnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six SnO6 octahedra. The corner-sharing octahedra tilt angles range from 56–71°. There are a spread of Sn–O bond distances ranging from 2.20–2.55 Å. In the eleventh Sn3+ site, Sn3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sn–O bond distances ranging from 2.32–2.73 Å. In the twelfth Sn3+ site, Sn3+ is bonded in a 3-coordinate geometry to three O2- atoms. There are two shorter (2.12 Å) and one longer (2.19 Å) Sn–O bond lengths. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded to two Mg2+ and two Sn3+ atoms to form a mixture of distorted corner and edge-sharing OMg2Sn2 trigonal pyramids. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+ and two equivalent Sn3+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+ and three Sn3+ atoms. In the fourth O2- site, O2- is bonded to four Sn3+ atoms to form distorted corner-sharing OSn4 trigonal pyramids. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Sn3+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+ and three Sn3+ atoms. In the seventh O2- site, O2- is bonded to one Mg2+ and three Sn3+ atoms to form distorted corner-sharing OMgSn3 tetrahedra. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent Sn3+ atoms. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Sn3+ atoms. In the tenth O2- site, O2- is bonded to two Mg2+ and two Sn3+ atoms to form a mixture of corner and edge-sharing OMg2Sn2 tetrahedra. In the eleventh O2- site, O2- is bonded to one Mg2+ and three Sn3+ atoms to form OMgSn3 tetrahedra that share corners with eight OMgSn3 tetrahedra and edges with two equivalent OMg2Sn2 tetrahedra. In the twelfth O2- site, O2- is bonded to two Mg2+ and two Sn3+ atoms to form a mixture of corner and edge-sharing OMg2Sn2 tetrahedra. In the thirteenth O2- site, O2- is bonded to one Mg2+ and three Sn3+ atoms to form a mixture of distorted corner and edge-sharing OMgSn3 tetrahedra. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and three Sn3+ atoms. In the fifteenth O2- site, O2- is bonded to one Mg2+ and three Sn3+ atoms to form OMgSn3 tetrahedra that share corners with twelve OMgSn3 tetrahedra and edges with three OMg2Sn2 tetrahedra. In the sixteenth O2- site, O2- is bonded to one Mg2+ and three Sn3+ atoms to form a mixture of corner and edge-sharing OMgSn3 tetrahedra. In the seventeenth O2- site, O2- is bonded to two Mg2+ and two Sn3+ atoms to form a mixture of corner and edge-sharing OMg2Sn2 tetrahedra. In the eighteenth O2- site, O2- is bonded to two Mg2+ and two Sn3+ atoms to form a mixture of corner and edge-sharing OMg2Sn2 tetrahedra. In the nineteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two equivalent Sn3+ atoms. In the twentieth O2- site, O2- is bonded to one Mg2+ and three Sn3+ atoms to form a mixture of distorted corner and edge-sharing OMgSn3 tetrahedra. In the twenty-first O2- site, O2- is bonded to one Mg2+ and three Sn3+ atoms to form OMgSn3 tetrahedra that share corners with eight OMgSn3 tetrahedra and edges with two equivalent OMg2Sn2 tetrahedra. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to four Sn3+ atoms. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+ and three Sn3+ atoms. In the twenty-fourth O2- site, O2- is bonded to one Mg2+ and three Sn3+ atoms to form distorted corner-sharing OMgSn3 tetrahedra.

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2020-05-02. Materials Data on Mg(SnO2)2 by Materials Project. https://doi.org/10.17188/1321251

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