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DOE OSTI · 1283255

Materials Data on K6Ba3Ta12(Si2O13)4 by Materials Project

Abstract

K6Ba3Ta12(Si2O13)4 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are four inequivalent K sites. In the first K site, K is bonded in a 6-coordinate geometry to thirteen O atoms. There are a spread of K–O bond distances ranging from 2.89–3.29 Å. In the second K site, K is bonded in a 4-coordinate geometry to four O atoms. There are two shorter (2.73 Å) and two longer (2.84 Å) K–O bond lengths. In the third K site, K is bonded in a 4-coordinate geometry to four O atoms. There are a spread of K–O bond distances ranging from 2.74–2.82 Å. In the fourth K site, K is bonded in a 6-coordinate geometry to thirteen O atoms. There are a spread of K–O bond distances ranging from 2.89–3.29 Å. There are two inequivalent Ba sites. In the first Ba site, Ba is bonded in a 6-coordinate geometry to thirteen O atoms. There are a spread of Ba–O bond distances ranging from 2.87–3.28 Å. In the second Ba site, Ba is bonded in a 6-coordinate geometry to thirteen O atoms. There are a spread of Ba–O bond distances ranging from 2.88–3.24 Å. There are four inequivalent Ta sites. In the first Ta site, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with four TaO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 1–32°. There are a spread of Ta–O bond distances ranging from 1.97–2.05 Å. In the second Ta site, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with four TaO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 1–32°. There are a spread of Ta–O bond distances ranging from 1.96–2.06 Å. In the third Ta site, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with four TaO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 3–32°. There are a spread of Ta–O bond distances ranging from 1.96–2.07 Å. In the fourth Ta site, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with four TaO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 2–32°. There are a spread of Ta–O bond distances ranging from 1.97–2.05 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three TaO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 25–29°. There are a spread of Si–O bond distances ranging from 1.61–1.64 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three TaO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 23–27°. There is one shorter (1.62 Å) and three longer (1.63 Å) Si–O bond length. There are twenty inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to two K and two Ta atoms. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Ba, one Ta, and one Si atom. In the third O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Ba, one Ta, and one Si atom. In the fourth O site, O is bonded in a distorted linear geometry to one K and two equivalent Si atoms. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to one Ba and two Ta atoms. In the sixth O site, O is bonded in a distorted bent 150 degrees geometry to two Ba, one Ta, and one Si atom. In the seventh O site, O is bonded in a linear geometry to one K, two equivalent Ba, and two equivalent Ta atoms. In the eighth O site, O is bonded in a distorted linear geometry to two equivalent Ta atoms. In the ninth O site, O is bonded in a distorted bent 150 degrees geometry to one Ba and two equivalent Ta atoms. In the tenth O site, O is bonded in a distorted linear geometry to two equivalent Ta atoms. In the eleventh O site, O is bonded in a linear geometry to one K, two Ba, and two equivalent Ta atoms. In the twelfth O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Ba, one Ta, and one Si atom. In the thirteenth O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Ba, one Ta, and one Si atom. In the fourteenth O site, O is bonded in a distorted linear geometry to two K and two equivalent Si atoms. In the fifteenth O site, O is bonded in a 2-coordinate geometry to two K, one Ta, and one Si atom. In the sixteenth O site, O is bonded in a linear geometry to two equivalent K, one Ba, and two equivalent Ta atoms. In the seventeenth O site, O is bonded in a linear geometry to two equivalent Ta atoms. In the eighteenth O site, O is bonded in a 2-coordinate geometry to two K and two equivalent Ta atoms. In the nineteenth O site, O is bonded in a distorted linear geometry to two equivalent Ta atoms. In the twentieth O site, O is bonded in a linear geometry to two K, one Ba, and two equivalent Ta atoms.

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2020-05-29. Materials Data on K6Ba3Ta12(Si2O13)4 by Materials Project. https://doi.org/10.17188/1283255

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