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DOE OSTI · 1264761

Materials Data on Al2CoCl8 by Materials Project

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Abstract

CoAl2Cl8 crystallizes in the monoclinic C2/c space group. The structure is one-dimensional and consists of two CoAl2Cl8 ribbons oriented in the (0, 0, 1) direction. Co2+ is bonded to six Cl1- atoms to form CoCl6 octahedra that share corners with two equivalent AlCl4 tetrahedra and edges with two equivalent AlCl4 tetrahedra. There are two shorter (2.46 Å) and four longer (2.48 Å) Co–Cl bond lengths. Al3+ is bonded to four Cl1- atoms to form AlCl4 tetrahedra that share a cornercorner with one CoCl6 octahedra and an edgeedge with one CoCl6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are one shorter (2.10 Å) and three longer (2.19 Å) Al–Cl bond lengths. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+ atom. In the second Cl1- site, Cl1- is bonded in an L-shaped geometry to one Co2+ and one Al3+ atom. In the third Cl1- site, Cl1- is bonded in a bent 120 degrees geometry to one Co2+ and one Al3+ atom. In the fourth Cl1- site, Cl1- is bonded in an L-shaped geometry to one Co2+ and one Al3+ atom.

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36 MATERIALS SCIENCEAl-Cl-CoAl2CoCl8crystal structure

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2020-07-20. Materials Data on Al2CoCl8 by Materials Project. https://doi.org/10.17188/1264761

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