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DOE OSTI · 1282569

Materials Data on KBa2As5 by Materials Project

Abstract

KBa2As5 is Magnesium tetraboride-derived structured and crystallizes in the monoclinic Cm 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 As1- atoms. There are a spread of K–As bond distances ranging from 3.31–3.56 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight As1- atoms. There are a spread of K–As bond distances ranging from 3.29–3.59 Å. In the third K1+ site, K1+ is bonded in a 8-coordinate geometry to eight As1- atoms. There are a spread of K–As bond distances ranging from 3.27–3.59 Å. In the fourth K1+ site, K1+ is bonded in a 9-coordinate geometry to nine As1- atoms. There are a spread of K–As bond distances ranging from 3.47–3.84 Å. There are eight inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine As1- atoms. There are a spread of Ba–As bond distances ranging from 3.47–3.73 Å. In the second Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight As1- atoms. There are a spread of Ba–As bond distances ranging from 3.33–3.42 Å. In the third Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to nine As1- atoms. There are a spread of Ba–As bond distances ranging from 3.38–3.77 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine As1- atoms. There are a spread of Ba–As bond distances ranging from 3.48–3.69 Å. In the fifth Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine As1- atoms. There are a spread of Ba–As bond distances ranging from 3.48–3.78 Å. In the sixth Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight As1- atoms. There are a spread of Ba–As bond distances ranging from 3.27–3.50 Å. In the seventh Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight As1- atoms. There are a spread of Ba–As bond distances ranging from 3.35–3.46 Å. In the eighth Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight As1- atoms. There are a spread of Ba–As bond distances ranging from 3.39–3.48 Å. There are sixteen inequivalent As1- sites. In the first As1- site, As1- is bonded to one K1+, four Ba2+, and two As1- atoms to form a mixture of distorted corner and face-sharing AsKBa4As2 pentagonal bipyramids. There are one shorter (2.47 Å) and one longer (2.52 Å) As–As bond lengths. In the second As1- site, As1- is bonded in a 5-coordinate geometry to two K1+, one Ba2+, and two equivalent As1- atoms. Both As–As bond lengths are 2.46 Å. In the third As1- site, As1- is bonded in a 7-coordinate geometry to one K1+, four Ba2+, and two As1- atoms. The As–As bond length is 2.53 Å. In the fourth As1- site, As1- is bonded in a 8-coordinate geometry to three K1+, three Ba2+, and two As1- atoms. There are one shorter (2.55 Å) and one longer (2.56 Å) As–As bond lengths. In the fifth As1- site, As1- is bonded in a 8-coordinate geometry to one K1+, five Ba2+, and two As1- atoms. The As–As bond length is 2.59 Å. In the sixth As1- site, As1- is bonded in a 7-coordinate geometry to two K1+, three Ba2+, and two As1- atoms. The As–As bond length is 2.47 Å. In the seventh As1- site, As1- is bonded in a 8-coordinate geometry to two equivalent K1+, four Ba2+, and two As1- atoms. The As–As bond length is 2.53 Å. In the eighth As1- site, As1- is bonded in a 8-coordinate geometry to two equivalent K1+, four Ba2+, and two As1- atoms. The As–As bond length is 2.53 Å. In the ninth As1- site, As1- is bonded to one K1+, four Ba2+, and two As1- atoms to form a mixture of distorted corner and face-sharing AsKBa4As2 pentagonal bipyramids. The As–As bond length is 2.46 Å. In the tenth As1- site, As1- is bonded in a 5-coordinate geometry to two K1+, one Ba2+, and two As1- atoms. In the eleventh As1- site, As1- is bonded in a 5-coordinate geometry to two K1+, two Ba2+, and two As1- atoms. There are one shorter (2.45 Å) and one longer (2.46 Å) As–As bond lengths. In the twelfth As1- site, As1- is bonded to one K1+, four Ba2+, and two As1- atoms to form distorted corner-sharing AsKBa4As2 pentagonal bipyramids. In the thirteenth As1- site, As1- is bonded in a 5-coordinate geometry to one K1+, two Ba2+, and two equivalent As1- atoms. In the fourteenth As1- site, As1- is bonded in a 7-coordinate geometry to one K1+, four Ba2+, and two As1- atoms. The As–As bond length is 2.54 Å. In the fifteenth As1- site, As1- is bonded in a 8-coordinate geometry to three K1+, three Ba2+, and two As1- atoms. The As–As bond length is 2.58 Å. In the sixteenth As1- site, As1- is bonded in a 8-coordinate geometry to one K1+, five Ba2+, and two As1- atoms. The As–As bond length is 2.59 Å.

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2020-04-29. Materials Data on KBa2As5 by Materials Project. https://doi.org/10.17188/1282569

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