Os2Al3 crystallizes in the tetragonal I4/mmm space group. Os(1) is bonded in a 9-coordinate geometry to four equivalent Al(1) and five equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a body-centered cubic geometry to eight equivalent Os(1) atoms. In the second Al site, Al(2) is bonded in a 4-coordinate geometry to five equivalent Os(1) atoms.
Os2Al3 crystallizes in the tetragonal I4/mmm space group. Os(1) is bonded in a 9-coordinate geometry to four equivalent Al(1) and five equivalent Al(2) atoms. All Os(1)-Al(1) bond lengths are 2.67 Å. There are four shorter (2.53 Å) and one longer (2.78 Å) Os(1)-Al(2) bond length. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a body-centered cubic geometry to eight equivalent Os(1) atoms. In the second Al site, Al(2) is bonded in a 4-coordinate geometry to five equivalent Os(1) atoms.