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DOE OSTI · 1696627

Materials Data on K7As2W8O39 by Materials Project

Abstract

K7W8As2O39 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are four inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.73–3.35 Å. In the second K site, K is bonded in a 6-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.65–3.43 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.74–3.35 Å. In the fourth K site, K is bonded in a 2-coordinate geometry to nine O atoms. There are a spread of K–O bond distances ranging from 2.66–3.27 Å. There are four inequivalent W sites. In the first W site, W is bonded to six O atoms to form distorted edge-sharing WO6 octahedra. There are a spread of W–O bond distances ranging from 1.78–2.32 Å. In the second W site, W is bonded in a 6-coordinate geometry to six O atoms. There are a spread of W–O bond distances ranging from 1.77–2.35 Å. In the third W site, W is bonded in a 6-coordinate geometry to six O atoms. There are a spread of W–O bond distances ranging from 1.76–2.37 Å. In the fourth W site, W is bonded in a 6-coordinate geometry to six O atoms. There are a spread of W–O bond distances ranging from 1.75–2.36 Å. There are two inequivalent As sites. In the first As site, As is bonded in a distorted trigonal non-coplanar geometry to three O atoms. There is one shorter (1.79 Å) and two longer (1.87 Å) As–O bond length. In the second As site, As is bonded in a trigonal non-coplanar geometry to three O atoms. There is one shorter (1.68 Å) and two longer (1.80 Å) As–O bond length. There are twenty-two inequivalent O sites. In the first O site, O is bonded in a 1-coordinate geometry to two K and one W atom. In the second O site, O is bonded in a bent 120 degrees geometry to two equivalent W atoms. In the third O site, O is bonded in a 1-coordinate geometry to one K, two equivalent W, and one As atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to one K and two W atoms. In the fifth O site, O is bonded in a 2-coordinate geometry to one K and one W atom. In the sixth O site, O is bonded in a 2-coordinate geometry to one K and one W atom. In the seventh O site, O is bonded in a 3-coordinate geometry to one K and two W atoms. In the eighth O site, O is bonded in a distorted rectangular see-saw-like geometry to three W and one As atom. In the ninth O site, O is bonded in a bent 120 degrees geometry to two W atoms. In the tenth O site, O is bonded in a bent 120 degrees geometry to two W atoms. In the eleventh O site, O is bonded in a distorted trigonal planar geometry to one K, one W, and one As atom. In the twelfth O site, O is bonded in a distorted bent 150 degrees geometry to one K and two equivalent W atoms. In the thirteenth O site, O is bonded in a 1-coordinate geometry to two K and one W atom. In the fourteenth O site, O is bonded in a 4-coordinate geometry to two K and two W atoms. In the fifteenth O site, O is bonded in a distorted bent 150 degrees geometry to one K and two equivalent W atoms. In the sixteenth O site, O is bonded in a single-bond geometry to two equivalent K and one As atom. In the seventeenth O site, O is bonded in a distorted bent 120 degrees geometry to two K and one W atom. In the eighteenth O site, O is bonded in a 4-coordinate geometry to three K and one W atom. In the nineteenth O site, O is bonded in a T-shaped geometry to three K atoms. In the twentieth O site, O is bonded in a 3-coordinate geometry to three K atoms. In the twenty-first O site, O is bonded in a water-like geometry to one K and one O atom. The O–O bond length is 1.23 Å. In the twenty-second O site, O is bonded in a distorted L-shaped geometry to two K atoms.

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2020-05-02. Materials Data on K7As2W8O39 by Materials Project. https://doi.org/10.17188/1696627

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