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DOE OSTI · 1756945

Materials Data on Ba7Ge39 by Materials Project

Abstract

Ba7Ge39 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are four inequivalent Ba sites. In the first Ba site, Ba is bonded in a 10-coordinate geometry to fifteen Ge atoms. There are a spread of Ba–Ge bond distances ranging from 3.45–3.80 Å. In the second Ba site, Ba is bonded in a 4-coordinate geometry to fourteen Ge atoms. There are a spread of Ba–Ge bond distances ranging from 3.46–3.67 Å. In the third Ba site, Ba is bonded in a 3-coordinate geometry to fifteen Ge atoms. There are a spread of Ba–Ge bond distances ranging from 3.46–3.78 Å. In the fourth Ba site, Ba is bonded in a 4-coordinate geometry to fourteen Ge atoms. There are a spread of Ba–Ge bond distances ranging from 3.44–3.71 Å. There are twenty-two inequivalent Ge sites. In the first Ge site, Ge is bonded to three Ba and four Ge atoms to form distorted corner-sharing GeBa3Ge4 hexagonal pyramids. There are a spread of Ge–Ge bond distances ranging from 2.55–2.64 Å. In the second Ge site, Ge is bonded in a 6-coordinate geometry to two equivalent Ba and four Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.55–2.60 Å. In the third Ge site, Ge is bonded in a 6-coordinate geometry to three Ba and three Ge atoms. Both Ge–Ge bond lengths are 2.59 Å. In the fourth Ge site, Ge is bonded in a 7-coordinate geometry to three Ba and four Ge atoms. Both Ge–Ge bond lengths are 2.66 Å. In the fifth Ge site, Ge is bonded in a distorted pentagonal planar geometry to two equivalent Ba and three Ge atoms. Both Ge–Ge bond lengths are 2.62 Å. In the sixth Ge site, Ge is bonded to three Ba and four Ge atoms to form a mixture of distorted edge, face, and corner-sharing GeBa3Ge4 hexagonal pyramids. There are a spread of Ge–Ge bond distances ranging from 2.61–2.65 Å. In the seventh Ge site, Ge is bonded in a 6-coordinate geometry to three Ba and three Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.58–2.64 Å. In the eighth Ge site, Ge is bonded in a 7-coordinate geometry to three Ba and four Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.59–2.61 Å. In the ninth Ge site, Ge is bonded in a 6-coordinate geometry to two Ba and four Ge atoms. There are one shorter (2.51 Å) and one longer (2.65 Å) Ge–Ge bond lengths. In the tenth Ge site, Ge is bonded to three Ba and four Ge atoms to form a mixture of distorted edge, face, and corner-sharing GeBa3Ge4 hexagonal pyramids. There are a spread of Ge–Ge bond distances ranging from 2.56–2.62 Å. In the eleventh Ge site, Ge is bonded to three Ba and four Ge atoms to form a mixture of distorted edge, face, and corner-sharing GeBa3Ge4 hexagonal pyramids. There are one shorter (2.55 Å) and one longer (2.63 Å) Ge–Ge bond lengths. In the twelfth Ge site, Ge is bonded in a 6-coordinate geometry to two Ba and four Ge atoms. There are one shorter (2.54 Å) and one longer (2.57 Å) Ge–Ge bond lengths. In the thirteenth Ge site, Ge is bonded in a 6-coordinate geometry to two Ba and four Ge atoms. There are one shorter (2.55 Å) and one longer (2.64 Å) Ge–Ge bond lengths. In the fourteenth Ge site, Ge is bonded in a 5-coordinate geometry to two Ba and four Ge atoms. The Ge–Ge bond length is 3.08 Å. In the fifteenth Ge site, Ge is bonded in a 6-coordinate geometry to two Ba and four Ge atoms. There are one shorter (2.52 Å) and one longer (2.61 Å) Ge–Ge bond lengths. In the sixteenth Ge site, Ge is bonded to three Ba and four Ge atoms to form a mixture of distorted edge and corner-sharing GeBa3Ge4 hexagonal pyramids. The Ge–Ge bond length is 2.55 Å. In the seventeenth Ge site, Ge is bonded to three Ba and four Ge atoms to form a mixture of distorted edge, face, and corner-sharing GeBa3Ge4 hexagonal pyramids. There are one shorter (2.62 Å) and one longer (2.69 Å) Ge–Ge bond lengths. In the eighteenth Ge site, Ge is bonded in a 6-coordinate geometry to two Ba and four Ge atoms. The Ge–Ge bond length is 2.70 Å. In the nineteenth Ge site, Ge is bonded in a 7-coordinate geometry to three Ba and four Ge atoms. The Ge–Ge bond length is 2.65 Å. In the twentieth Ge site, Ge is bonded in a 5-coordinate geometry to three Ba and four Ge atoms. The Ge–Ge bond length is 3.12 Å. In the twenty-first Ge site, Ge is bonded in a 7-coordinate geometry to two Ba and five Ge atoms. In the twenty-second Ge site, Ge is bonded in a 6-coordinate geometry to three Ba and three Ge atoms.

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2020-09-03. Materials Data on Ba7Ge39 by Materials Project. https://doi.org/10.17188/1756945

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