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DOE OSTI · 1718298

Materials Data on K4Te8O23 by Materials Project

Abstract

K4Te8O23 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 3.03–3.34 Å. In the second K1+ site, K1+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.99–3.38 Å. In the third K1+ site, K1+ is bonded in a 1-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.80–3.35 Å. In the fourth K1+ site, K1+ is bonded in a 2-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.81–3.45 Å. There are eight inequivalent Te+5.25+ sites. In the first Te+5.25+ site, Te+5.25+ is bonded to five O2- atoms to form distorted corner-sharing TeO5 square pyramids. The corner-sharing octahedra tilt angles range from 43–62°. There are a spread of Te–O bond distances ranging from 1.85–2.24 Å. In the second Te+5.25+ site, Te+5.25+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with four TeO6 octahedra and corners with two TeO5 square pyramids. The corner-sharing octahedra tilt angles range from 40–49°. There are a spread of Te–O bond distances ranging from 1.90–2.01 Å. In the third Te+5.25+ site, Te+5.25+ is bonded to six O2- atoms to form corner-sharing TeO6 octahedra. The corner-sharing octahedra tilt angles range from 41–64°. There are a spread of Te–O bond distances ranging from 1.89–2.00 Å. In the fourth Te+5.25+ site, Te+5.25+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with two equivalent TeO6 octahedra and corners with four TeO5 square pyramids. The corner-sharing octahedral tilt angles are 44°. There are a spread of Te–O bond distances ranging from 1.94–2.00 Å. In the fifth Te+5.25+ site, Te+5.25+ is bonded to six O2- atoms to form distorted TeO6 octahedra that share corners with five TeO6 octahedra and a cornercorner with one TeO5 square pyramid. The corner-sharing octahedra tilt angles range from 43–64°. There are a spread of Te–O bond distances ranging from 1.99–2.61 Å. In the sixth Te+5.25+ site, Te+5.25+ is bonded to five O2- atoms to form distorted corner-sharing TeO5 square pyramids. The corner-sharing octahedra tilt angles range from 42–64°. There are a spread of Te–O bond distances ranging from 1.94–2.21 Å. In the seventh Te+5.25+ site, Te+5.25+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with four TeO6 octahedra and corners with two TeO5 square pyramids. The corner-sharing octahedra tilt angles range from 40–48°. There are a spread of Te–O bond distances ranging from 1.90–2.01 Å. In the eighth Te+5.25+ site, Te+5.25+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with five TeO6 octahedra and a cornercorner with one TeO5 square pyramid. The corner-sharing octahedra tilt angles range from 43–47°. There are a spread of Te–O bond distances ranging from 1.94–1.96 Å. There are twenty-three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+ and two Te+5.25+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two K1+ and two Te+5.25+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one K1+ and two Te+5.25+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Te+5.25+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+ and two Te+5.25+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Te+5.25+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one K1+ and two Te+5.25+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Te+5.25+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two Te+5.25+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two equivalent Te+5.25+ atoms. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+ and two Te+5.25+ atoms. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two Te+5.25+ atoms. In the thirteenth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two Te+5.25+ atoms. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two K1+ and two Te+5.25+ atoms. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Te+5.25+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+ and two equivalent Te+5.25+ atoms. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Te+5.25+ atoms. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Te+5.25+ atoms. In the nineteenth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two Te+5.25+ atoms. In the twentieth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two Te+5.25+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+ and two Te+5.25+ atoms. In the twenty-second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+ and two Te+5.25+ atoms. In the twenty-third O2- site, O2- is bonded in a 1-coordinate geometry to two K1+ and two Te+5.25+ atoms.

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2020-04-29. Materials Data on K4Te8O23 by Materials Project. https://doi.org/10.17188/1718298

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