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DOE OSTI · 1745571

Materials Data on Ca4Mg4V3AsO20 by Materials Project

Abstract

Ca4Mg4V3AsO20 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Ca sites. In the first Ca site, Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.28–2.66 Å. In the second Ca site, Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.68 Å. In the third Ca site, Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.76 Å. In the fourth Ca site, Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.68 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share a cornercorner with one AsO4 tetrahedra, corners with three VO4 tetrahedra, and edges with two equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.16 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share a cornercorner with one AsO4 tetrahedra, corners with three VO4 tetrahedra, and edges with two equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.99–2.14 Å. In the third Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share a cornercorner with one AsO4 tetrahedra, corners with three VO4 tetrahedra, and edges with two equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.99–2.16 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share a cornercorner with one AsO4 tetrahedra, corners with three VO4 tetrahedra, and edges with two equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.99–2.16 Å. There are three inequivalent V sites. In the first V site, V is bonded to four O atoms to form VO4 tetrahedra that share corners with four MgO6 octahedra. The corner-sharing octahedra tilt angles range from 41–58°. There are a spread of V–O bond distances ranging from 1.71–1.77 Å. In the second V site, V is bonded to four O atoms to form VO4 tetrahedra that share corners with four MgO6 octahedra. The corner-sharing octahedra tilt angles range from 41–58°. There are a spread of V–O bond distances ranging from 1.71–1.77 Å. In the third V site, V is bonded to four O atoms to form VO4 tetrahedra that share corners with four MgO6 octahedra. The corner-sharing octahedra tilt angles range from 41–58°. There are a spread of V–O bond distances ranging from 1.72–1.78 Å. As is bonded to four O atoms to form AsO4 tetrahedra that share corners with four MgO6 octahedra. The corner-sharing octahedra tilt angles range from 41–58°. There are a spread of As–O bond distances ranging from 1.72–1.75 Å. There are twenty inequivalent O sites. In the first O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one As atom. In the second O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one V atom. In the third O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one V atom. In the fourth O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one V atom. In the fifth O site, O is bonded in a 3-coordinate geometry to two Ca and one As atom. In the sixth O site, O is bonded in a 1-coordinate geometry to two Ca and one V atom. In the seventh O site, O is bonded in a 1-coordinate geometry to two Ca and one V atom. In the eighth O site, O is bonded in a 1-coordinate geometry to two Ca and one V atom. In the ninth O site, O is bonded in a trigonal non-coplanar geometry to one Ca and two Mg atoms. In the tenth O site, O is bonded in a trigonal non-coplanar geometry to one Ca and two Mg atoms. In the eleventh O site, O is bonded in a trigonal non-coplanar geometry to one Ca and two Mg atoms. In the twelfth O site, O is bonded in a trigonal non-coplanar geometry to one Ca and two Mg atoms. In the thirteenth O site, O is bonded to one Ca, two Mg, and one As atom to form distorted corner-sharing OCaMg2As trigonal pyramids. In the fourteenth O site, O is bonded to one Ca, two Mg, and one V atom to form distorted corner-sharing OCaMg2V trigonal pyramids. In the fifteenth O site, O is bonded to one Ca, two Mg, and one V atom to form distorted corner-sharing OCaMg2V trigonal pyramids. In the sixteenth O site, O is bonded to one Ca, two Mg, and one V atom to form distorted corner-sharing OCaMg2V trigonal pyramids. In the seventeenth O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one As atom. In the eighteenth O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one V atom. In the nineteenth O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one V atom. In the twentieth O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one V atom.

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2020-05-02. Materials Data on Ca4Mg4V3AsO20 by Materials Project. https://doi.org/10.17188/1745571

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36 MATERIALS SCIENCE↗