Materials Data on Sr3(AlSn)2 by Materials Project
Sr3(AlSn)2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 7-coordinate geometry to two equivalent Al and five equivalent Sn atoms. Both Sr–Al bond lengths are 3.45 Å. There are four shorter (3.46 Å) and one longer (3.53 Å) Sr–Sn bond lengths. In the second Sr site, Sr is bonded to eight equivalent Al and four equivalent Sn atoms to form a mixture of edge and face-sharing SrAl8Sn4 cuboctahedra. All Sr–Al bond lengths are 3.59 Å. All Sr–Sn bond lengths are 3.78 Å. Al is bonded in a 2-coordinate geometry to six Sr, one Al, and two equivalent Sn atoms. The Al–Al bond length is 2.54 Å. Both Al–Sn bond lengths are 2.75 Å. Sn is bonded in a 9-coordinate geometry to seven Sr and two equivalent Al atoms.