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DOE OSTI · 1673001

Materials Data on Nb24Ge7Te48 by Materials Project

Abstract

(Nb3GeTe6)4(Nb4GeTe8)3 crystallizes in the monoclinic Cm space group. The structure is two-dimensional and consists of two Nb3GeTe6 sheets oriented in the (0, 1, 0) direction and two Nb4GeTe8 sheets oriented in the (0, 1, 0) direction. In each Nb3GeTe6 sheet, there are six inequivalent Nb+2.83+ sites. In the first Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.84–2.96 Å. In the second Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.78–2.98 Å. In the third Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.83–2.96 Å. In the fourth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.79–2.98 Å. In the fifth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form distorted edge-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.82–2.92 Å. In the sixth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form distorted edge-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.81–2.92 Å. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded in a square co-planar geometry to four Te2- atoms. There are a spread of Ge–Te bond distances ranging from 2.81–2.87 Å. In the second Ge4+ site, Ge4+ is bonded in a square co-planar geometry to four Te2- atoms. There are two shorter (2.81 Å) and two longer (2.86 Å) Ge–Te bond lengths. There are twelve inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the second Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the third Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the fourth Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the fifth Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the sixth Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the seventh Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the eighth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the ninth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the tenth Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the eleventh Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the twelfth Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In each Nb4GeTe8 sheet, there are twelve inequivalent Nb+2.83+ sites. In the first Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form distorted edge-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.82–2.86 Å. In the second Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form distorted edge-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.81–2.93 Å. In the third Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.76–3.00 Å. In the fourth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.78–2.97 Å. In the fifth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form distorted edge-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.83–2.91 Å. In the sixth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.80–3.00 Å. In the seventh Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.81–2.90 Å. In the eighth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form distorted edge-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.81–2.91 Å. In the ninth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.81–2.89 Å. In the tenth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.84–2.98 Å. In the eleventh Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.81–2.98 Å. In the twelfth Nb+2.83+ site, Nb+2.83+ is bonded to six Te2- atoms to form a mixture of distorted edge and face-sharing NbTe6 pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.85–2.96 Å. There are three inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded in a square co-planar geometry to four Te2- atoms. There are two shorter (2.81 Å) and two longer (2.87 Å) Ge–Te bond lengths. In the second Ge4+ site, Ge4+ is bonded in a distorted square co-planar geometry to four Te2- atoms. There are two shorter (2.81 Å) and two longer (2.90 Å) Ge–Te bond lengths. In the third Ge4+ site, Ge4+ is bonded in a square co-planar geometry to four Te2- atoms. There are two shorter (2.80 Å) and two longer (2.84 Å) Ge–Te bond lengths. There are twelve inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the second Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the third Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the fourth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the fifth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the sixth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the seventh Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the eighth Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the ninth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+2.83+ atoms. In the tenth Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the eleventh Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom. In the twelfth Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+2.83+ and one Ge4+ atom.

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2020-05-02. Materials Data on Nb24Ge7Te48 by Materials Project. https://doi.org/10.17188/1673001

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