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DOE OSTI · 1751198

Materials Data on Na2Li18Ge17 by Materials Project

Abstract

Na2Li18Ge17 crystallizes in the trigonal P31m space group. The structure is three-dimensional. there are three inequivalent Na sites. In the first Na site, Na is bonded in a 4-coordinate geometry to four Ge atoms. There are a spread of Na–Ge bond distances ranging from 2.90–3.19 Å. In the second Na site, Na is bonded in a distorted single-bond geometry to four Ge atoms. There are one shorter (3.01 Å) and three longer (3.37 Å) Na–Ge bond lengths. In the third Na site, Na is bonded in a 1-coordinate geometry to four Ge atoms. There are one shorter (3.04 Å) and three longer (3.35 Å) Na–Ge bond lengths. There are thirteen inequivalent Li sites. In the first Li site, Li is bonded in a 12-coordinate geometry to four Li and twelve Ge atoms. There are a spread of Li–Li bond distances ranging from 2.97–3.04 Å. There are a spread of Li–Ge bond distances ranging from 2.98–3.10 Å. In the second Li site, Li is bonded in a 9-coordinate geometry to one Li and nine Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.95–3.05 Å. In the third Li site, Li is bonded in a 9-coordinate geometry to one Li and nine Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.87–3.07 Å. In the fourth Li site, Li is bonded in a 8-coordinate geometry to one Li and eight Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.88–3.02 Å. In the fifth Li site, Li is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.79–2.86 Å. In the sixth Li site, Li is bonded in a 4-coordinate geometry to four Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.55–2.69 Å. In the seventh Li site, Li is bonded to four Ge atoms to form distorted corner-sharing LiGe4 tetrahedra. There are a spread of Li–Ge bond distances ranging from 2.74–2.92 Å. In the eighth Li site, Li is bonded in a 12-coordinate geometry to six Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.78–3.12 Å. In the ninth Li site, Li is bonded in a 4-coordinate geometry to four Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.60–2.88 Å. In the tenth Li site, Li is bonded in a 4-coordinate geometry to five Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.80–3.14 Å. In the eleventh Li site, Li is bonded in a 4-coordinate geometry to four Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.57–2.74 Å. In the twelfth Li site, Li is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.89–2.98 Å. In the thirteenth Li site, Li is bonded to four Ge atoms to form a mixture of distorted edge and corner-sharing LiGe4 tetrahedra. There are a spread of Li–Ge bond distances ranging from 2.60–2.95 Å. There are twelve inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to one Na and nine Li atoms. In the second Ge site, Ge is bonded in a 1-coordinate geometry to one Na, six Li, and three Ge atoms. There are two shorter (2.60 Å) and one longer (2.61 Å) Ge–Ge bond lengths. In the third Ge site, Ge is bonded in a 10-coordinate geometry to one Na, six Li, and three equivalent Ge atoms. In the fourth Ge site, Ge is bonded in a 11-coordinate geometry to one Na, seven Li, and three Ge atoms. There are one shorter (2.61 Å) and two longer (2.62 Å) Ge–Ge bond lengths. In the fifth Ge site, Ge is bonded in a 7-coordinate geometry to one Na, six Li, and three equivalent Ge atoms. In the sixth Ge site, Ge is bonded in a 10-coordinate geometry to seven Li and three Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.52–2.70 Å. In the seventh Ge site, Ge is bonded in a 9-coordinate geometry to six Li and three Ge atoms. There are one shorter (2.53 Å) and one longer (2.60 Å) Ge–Ge bond lengths. In the eighth Ge site, Ge is bonded in a 9-coordinate geometry to six Li and three Ge atoms. There are one shorter (2.60 Å) and one longer (2.73 Å) Ge–Ge bond lengths. In the ninth Ge site, Ge is bonded in a 10-coordinate geometry to one Na, six Li, and three Ge atoms. The Ge–Ge bond length is 2.53 Å. In the tenth Ge site, Ge is bonded in a 9-coordinate geometry to one Na, five Li, and three Ge atoms. The Ge–Ge bond length is 2.51 Å. In the eleventh Ge site, Ge is bonded in a 1-coordinate geometry to seven Li and three Ge atoms. Both Ge–Ge bond lengths are 2.62 Å. In the twelfth Ge site, Ge is bonded in a 10-coordinate geometry to seven Li and three Ge atoms. The Ge–Ge bond length is 2.63 Å.

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2020-04-30. Materials Data on Na2Li18Ge17 by Materials Project. https://doi.org/10.17188/1751198

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