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DOE OSTI · 1729611

Materials Data on Er12(ReC3)5 by Materials Project

Abstract

Er12(ReC3)5 crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. there are three inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to five C+3.47- atoms to form distorted ErC5 square pyramids that share corners with three equivalent ErC5 square pyramids, edges with four equivalent ErC8 hexagonal bipyramids, and an edgeedge with one ErC5 square pyramid. There are a spread of Er–C bond distances ranging from 2.31–2.54 Å. In the second Er3+ site, Er3+ is bonded to eight C+3.47- atoms to form distorted ErC8 hexagonal bipyramids that share corners with four equivalent ErC8 hexagonal bipyramids, edges with two equivalent ErC8 hexagonal bipyramids, and edges with eight equivalent ErC5 square pyramids. There are a spread of Er–C bond distances ranging from 2.54–2.78 Å. In the third Er3+ site, Er3+ is bonded in a rectangular see-saw-like geometry to four C+3.47- atoms. There are two shorter (2.49 Å) and two longer (2.52 Å) Er–C bond lengths. There are two inequivalent Re+3.20+ sites. In the first Re+3.20+ site, Re+3.20+ is bonded in a distorted T-shaped geometry to three C+3.47- atoms. There are one shorter (1.94 Å) and two longer (2.06 Å) Re–C bond lengths. In the second Re+3.20+ site, Re+3.20+ is bonded in a trigonal planar geometry to three equivalent C+3.47- atoms. All Re–C bond lengths are 1.91 Å. There are four inequivalent C+3.47- sites. In the first C+3.47- site, C+3.47- is bonded to five Er3+ and one Re+3.20+ atom to form a mixture of distorted corner and edge-sharing CEr5Re octahedra. The corner-sharing octahedra tilt angles range from 5–45°. In the second C+3.47- site, C+3.47- is bonded in a 6-coordinate geometry to four Er3+, one Re+3.20+, and one C+3.47- atom. The C–C bond length is 1.36 Å. In the third C+3.47- site, C+3.47- is bonded in a 5-coordinate geometry to four Er3+ and one C+3.47- atom. In the fourth C+3.47- site, C+3.47- is bonded to four Er3+ and two equivalent Re+3.20+ atoms to form CEr4Re2 octahedra that share corners with four equivalent CEr4Re2 octahedra and edges with four equivalent CEr5Re octahedra. The corner-sharing octahedra tilt angles range from 6–26°.

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2020-05-04. Materials Data on Er12(ReC3)5 by Materials Project. https://doi.org/10.17188/1729611

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