Materials Data on Ca6Al43W4 by Materials Project

Abstract

Ca6W4Al43 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. Ca is bonded in a 6-coordinate geometry to one Ca, one W, and fifteen Al atoms. The Ca–Ca bond length is 3.45 Å. The Ca–W bond length is 3.51 Å. There are a spread of Ca–Al bond distances ranging from 3.10–3.43 Å. There are two inequivalent W sites. In the first W site, W is bonded in a 10-coordinate geometry to two equivalent Ca and ten Al atoms. There are a spread of W–Al bond distances ranging from 2.60–2.73 Å. In the second W site, W is bonded in a cuboctahedral geometry to twelve Al atoms. There are six shorter (2.70 Å) and six longer (2.85 Å) W–Al bond lengths. There are seven inequivalent Al sites. In the first Al site, Al is bonded in a 1-coordinate geometry to two equivalent Ca, one W, and nine Al atoms. There are a spread of Al–Al bond distances ranging from 2.77–3.02 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to four equivalent Ca and six Al atoms. There are two shorter (2.79 Å) and two longer (2.88 Å) Al–Al bond lengths. In the third Al site, Al is bonded in a 1-coordinate geometry to two equivalent Ca, one W, and two Al atoms. The Al–Al bond length is 2.76 Å. In the fourth Al site, Al is bonded in a distorted linear geometry to two equivalent W atoms. In the fifth Al site, Al is bonded in a 2-coordinate geometry to one Ca, two W, and three equivalent Al atoms. In the sixth Al site, Al is bonded to three equivalent Ca and nine Al atoms to form a mixture of face and corner-sharing AlCa3Al9 cuboctahedra. All Al–Al bond lengths are 2.84 Å. In the seventh Al site, Al is bonded in a 1-coordinate geometry to two equivalent Ca, one W, and two equivalent Al atoms.