Materials Data on SmAlSi by Materials Project
AlSiSm is hexagonal omega structure-derived structured and crystallizes in the tetragonal I4_1md space group. The structure is three-dimensional. Sm is bonded to six equivalent Al and six equivalent Si atoms to form a mixture of edge and face-sharing SmAl6Si6 cuboctahedra. There are two shorter (3.19 Å) and four longer (3.20 Å) Sm–Al bond lengths. There are four shorter (3.19 Å) and two longer (3.22 Å) Sm–Si bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a distorted trigonal planar geometry to six equivalent Sm and three equivalent Si atoms. There are one shorter (2.41 Å) and two longer (2.42 Å) Al–Si bond lengths. In the second Al site, Al is bonded in a distorted trigonal planar geometry to six equivalent Sm and three equivalent Si atoms. There are two shorter (3.19 Å) and four longer (3.20 Å) Al–Sm bond lengths. There are one shorter (2.41 Å) and two longer (2.42 Å) Al–Si bond lengths. Si is bonded in a distorted trigonal planar geometry to six equivalent Sm and three Al atoms.