Materials Data on CaAl9Co2 by Materials Project
CaCo2Al9 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Ca is bonded to twelve equivalent Al atoms to form face-sharing CaAl12 cuboctahedra. All Ca–Al bond lengths are 3.49 Å. Co is bonded in a 9-coordinate geometry to nine Al atoms. There are three shorter (2.28 Å) and six longer (2.54 Å) Co–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a linear geometry to two equivalent Co atoms. In the second Al site, Al is bonded in a 2-coordinate geometry to two equivalent Ca and two equivalent Co atoms.
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