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DOE OSTI · 1281500

Materials Data on Mg(GaS2)2 by Materials Project

Abstract

MgGa2S4 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 six S2- atoms to form MgS6 octahedra that share corners with ten GaS4 tetrahedra and edges with three MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.59–2.71 Å. In the second Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with six GaS4 tetrahedra and edges with six MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.54–2.61 Å. In the third Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with six GaS4 tetrahedra and edges with six MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.54–2.61 Å. In the fourth Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with ten GaS4 tetrahedra and edges with three MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.59–2.70 Å. In the fifth Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with eight GaS4 tetrahedra and edges with five MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.55–2.73 Å. In the sixth Mg2+ site, Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with eight GaS4 tetrahedra and edges with five MgS6 octahedra. There are a spread of Mg–S bond distances ranging from 2.54–2.73 Å. There are twelve inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three MgS6 octahedra and corners with six GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–63°. There are a spread of Ga–S bond distances ranging from 2.20–2.36 Å. In the second Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with four MgS6 octahedra and corners with five GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Ga–S bond distances ranging from 2.25–2.38 Å. In the third Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three MgS6 octahedra and corners with six GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–63°. There are a spread of Ga–S bond distances ranging from 2.20–2.36 Å. In the fourth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with four MgS6 octahedra and corners with five GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Ga–S bond distances ranging from 2.24–2.38 Å. In the fifth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with four MgS6 octahedra and corners with five GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–64°. There are a spread of Ga–S bond distances ranging from 2.24–2.38 Å. In the sixth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with five MgS6 octahedra, corners with three GaS4 tetrahedra, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–63°. There are a spread of Ga–S bond distances ranging from 2.24–2.35 Å. In the seventh Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three MgS6 octahedra and corners with six GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–63°. There are a spread of Ga–S bond distances ranging from 2.21–2.36 Å. In the eighth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with five MgS6 octahedra, corners with three GaS4 tetrahedra, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–62°. There are a spread of Ga–S bond distances ranging from 2.24–2.35 Å. In the ninth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three MgS6 octahedra and corners with six GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–63°. There are a spread of Ga–S bond distances ranging from 2.21–2.36 Å. In the tenth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with four MgS6 octahedra and corners with five GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Ga–S bond distances ranging from 2.25–2.38 Å. In the eleventh Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with five MgS6 octahedra, corners with three GaS4 tetrahedra, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–62°. There are a spread of Ga–S bond distances ranging from 2.24–2.35 Å. In the twelfth Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with five MgS6 octahedra, corners with three GaS4 tetrahedra, and an edgeedge with one GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–63°. There are a spread of Ga–S bond distances ranging from 2.24–2.35 Å. There are twenty-four inequivalent S2- sites. In the first S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the second S2- site, S2- is bonded in a 4-coordinate geometry to two Mg2+ and two Ga3+ atoms. In the third S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the fourth S2- site, S2- is bonded in a trigonal planar geometry to one Mg2+ and two Ga3+ atoms. In the fifth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the sixth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the seventh S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the eighth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the ninth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the tenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the eleventh S2- site, S2- is bonded in a trigonal planar geometry to one Mg2+ and two Ga3+ atoms. In the twelfth S2- site, S2- is bonded in a trigonal planar geometry to one Mg2+ and two Ga3+ atoms. In the thirteenth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the fourteenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the fifteenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the sixteenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the seventeenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the eighteenth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Ga3+ atoms. In the nineteenth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the twentieth S2- site, S2- is bonded to three Mg2+ and one Ga3+ atom to form a mixture of distorted edge and corner-sharing SMg3Ga trigonal pyramids. In the twenty-first S2- site, S2- is bonded in a trigonal planar geometry to one Mg2+ and two Ga3+ atoms. In the twenty-second S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the twenty-third S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms. In the twenty-fourth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Ga3+ atoms.

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2020-04-29. Materials Data on Mg(GaS2)2 by Materials Project. https://doi.org/10.17188/1281500

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