Materials Data on Sm6Al43Cr4 by Materials Project

Abstract

Sm6Cr4Al43 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. Sm is bonded in a 6-coordinate geometry to one Sm, one Cr, and fifteen Al atoms. The Sm–Sm bond length is 3.44 Å. The Sm–Cr bond length is 3.54 Å. There are a spread of Sm–Al bond distances ranging from 3.06–3.49 Å. There are two inequivalent Cr sites. In the first Cr site, Cr is bonded in a 10-coordinate geometry to two equivalent Sm and ten Al atoms. There are a spread of Cr–Al bond distances ranging from 2.53–2.67 Å. In the second Cr site, Cr is bonded in a cuboctahedral geometry to twelve Al atoms. There are six shorter (2.66 Å) and six longer (2.79 Å) Cr–Al bond lengths. There are seven inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to one Sm, two Cr, and nine Al atoms. There are a spread of Al–Al bond distances ranging from 2.72–2.95 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to four equivalent Sm and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.76–3.13 Å. In the third Al site, Al is bonded in a 12-coordinate geometry to two equivalent Sm, one Cr, and nine Al atoms. There are a spread of Al–Al bond distances ranging from 2.75–3.02 Å. In the fourth Al site, Al is bonded in a 12-coordinate geometry to two equivalent Cr and ten Al atoms. Both Al–Al bond lengths are 2.76 Å. In the fifth Al site, Al is bonded in a 12-coordinate geometry to two equivalent Sm, one Cr, and nine Al atoms. Both Al–Al bond lengths are 2.95 Å. In the sixth Al site, Al is bonded to three equivalent Sm and nine Al atoms to form a mixture of face and corner-sharing AlSm3Al9 cuboctahedra. All Al–Al bond lengths are 2.82 Å. In the seventh Al site, Al is bonded in a 10-coordinate geometry to two equivalent Sm, one Cr, and seven Al atoms. The Al–Al bond length is 2.75 Å.