Sr3(AlGe)2 crystallizes in the orthorhombic Immm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to two equivalent Al(1) and five equivalent Ge(1) atoms. In the second Sr site, Sr(2) is bonded to eight equivalent Al(1) and four equivalent Ge(1) atoms to form a mixture of face and edge-sharing SrAl8Ge4 cuboctahedra. Al(1) is bonded in a 9-coordinate geometry to two equivalent Sr(1), four equivalent Sr(2), one Al(1), and two equivalent Ge(1) atoms. Ge(1) is bonded in a 9-coordinate geometry to two equivalent Sr(2), five equivalent Sr(1), and two equivalent Al(1) atoms.
Sr3(AlGe)2 crystallizes in the orthorhombic Immm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to two equivalent Al(1) and five equivalent Ge(1) atoms. Both Sr(1)-Al(1) bond lengths are 3.33 Å. There are four shorter (3.33 Å) and one longer (3.37 Å) Sr(1)-Ge(1) bond length. In the second Sr site, Sr(2) is bonded to eight equivalent Al(1) and four equivalent Ge(1) atoms to form a mixture of face and edge-sharing SrAl8Ge4 cuboctahedra. All Sr(2)-Al(1) bond lengths are 3.47 Å. All Sr(2)-Ge(1) bond lengths are 3.64 Å. Al(1) is bonded in a 9-coordinate geometry to two equivalent Sr(1), four equivalent Sr(2), one Al(1), and two equivalent Ge(1) atoms. The Al(1)-Al(1) bond length is 2.56 Å. Both Al(1)-Ge(1) bond lengths are 2.55 Å. Ge(1) is bonded in a 9-coordinate geometry to two equivalent Sr(2), five equivalent Sr(1), and two equivalent Al(1) atoms.