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DOE OSTI · 1283638

Materials Data on K4Pb9 by Materials Project

Abstract

K4Pb9 is Magnesium tetraboride-like structured and crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are five inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight Pb atoms. There are a spread of K–Pb bond distances ranging from 3.71–4.06 Å. In the second K site, K is bonded in a 7-coordinate geometry to seven Pb atoms. There are a spread of K–Pb bond distances ranging from 3.75–3.90 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight Pb atoms. There are a spread of K–Pb bond distances ranging from 3.66–4.01 Å. In the fourth K site, K is bonded in a 8-coordinate geometry to eight Pb atoms. There are a spread of K–Pb bond distances ranging from 3.70–4.13 Å. In the fifth K site, K is bonded in a 7-coordinate geometry to seven Pb atoms. There are a spread of K–Pb bond distances ranging from 3.59–3.78 Å. There are twelve inequivalent Pb sites. In the first Pb site, Pb is bonded in a distorted body-centered cubic geometry to four K and four Pb atoms. There are two shorter (3.17 Å) and two longer (3.20 Å) Pb–Pb bond lengths. In the second Pb site, Pb is bonded in a 1-coordinate geometry to three K and five Pb atoms. There are a spread of Pb–Pb bond distances ranging from 3.15–3.52 Å. In the third Pb site, Pb is bonded in a 9-coordinate geometry to four K and five Pb atoms. There are two shorter (3.26 Å) and two longer (3.28 Å) Pb–Pb bond lengths. In the fourth Pb site, Pb is bonded in a 1-coordinate geometry to three K and five Pb atoms. There are a spread of Pb–Pb bond distances ranging from 3.15–3.48 Å. In the fifth Pb site, Pb is bonded in a 1-coordinate geometry to two K and four Pb atoms. There are a spread of Pb–Pb bond distances ranging from 3.16–3.23 Å. In the sixth Pb site, Pb is bonded in a 8-coordinate geometry to four K and four Pb atoms. There are one shorter (3.18 Å) and one longer (3.19 Å) Pb–Pb bond lengths. In the seventh Pb site, Pb is bonded in a 6-coordinate geometry to three K and three Pb atoms. There are one shorter (3.14 Å) and two longer (3.20 Å) Pb–Pb bond lengths. In the eighth Pb site, Pb is bonded in a 8-coordinate geometry to four K and four Pb atoms. There are one shorter (3.16 Å) and one longer (3.21 Å) Pb–Pb bond lengths. In the ninth Pb site, Pb is bonded in a 1-coordinate geometry to five K and four Pb atoms. In the tenth Pb site, Pb is bonded in a 2-coordinate geometry to three K and four Pb atoms. In the eleventh Pb site, Pb is bonded in a 1-coordinate geometry to four K and four Pb atoms. There are one shorter (3.16 Å) and one longer (3.23 Å) Pb–Pb bond lengths. In the twelfth Pb site, Pb is bonded in a 7-coordinate geometry to three K and four Pb atoms. The Pb–Pb bond length is 3.20 Å.

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2020-04-30. Materials Data on K4Pb9 by Materials Project. https://doi.org/10.17188/1283638

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36 MATERIALS SCIENCE↗