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DOE OSTI · 1276067

Materials Data on Fe11Mo6C5 by Materials Project

Abstract

Mo6Fe11C5 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Mo sites. In the first Mo site, Mo is bonded in a 2-coordinate geometry to one Fe and three C atoms. The Mo–Fe bond length is 2.71 Å. There are a spread of Mo–C bond distances ranging from 2.08–2.38 Å. In the second Mo site, Mo is bonded in a 2-coordinate geometry to one Fe and two equivalent C atoms. The Mo–Fe bond length is 2.78 Å. Both Mo–C bond lengths are 2.20 Å. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded in a distorted water-like geometry to one Fe and two equivalent C atoms. The Fe–Fe bond length is 2.48 Å. There are one shorter (1.99 Å) and one longer (2.09 Å) Fe–C bond lengths. In the second Fe site, Fe is bonded in a distorted bent 150 degrees geometry to one Fe and two equivalent C atoms. The Fe–Fe bond length is 2.49 Å. Both Fe–C bond lengths are 1.94 Å. In the third Fe site, Fe is bonded in a single-bond geometry to one C atom. The Fe–C bond length is 1.93 Å. In the fourth Fe site, Fe is bonded in a bent 150 degrees geometry to two equivalent C atoms. Both Fe–C bond lengths are 1.98 Å. In the fifth Fe site, Fe is bonded to six Mo and six Fe atoms to form FeFe6Mo6 cuboctahedra that share edges with two equivalent CFe2Mo4 octahedra. There are two inequivalent C sites. In the first C site, C is bonded in a 7-coordinate geometry to three Mo and four Fe atoms. In the second C site, C is bonded to four equivalent Mo and two equivalent Fe atoms to form CFe2Mo4 octahedra that share edges with two equivalent FeFe6Mo6 cuboctahedra.

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2020-07-15. Materials Data on Fe11Mo6C5 by Materials Project. https://doi.org/10.17188/1276067

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36 MATERIALS SCIENCE↗