BaAl2Ge2 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 16-coordinate geometry to four equivalent Al(2), five equivalent Al(1), three equivalent Ge(1), and four equivalent Ge(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to five equivalent Ba(1), one Ge(2), and three equivalent Ge(1) atoms to form distorted AlBa5Ge4 tetrahedra that share corners with eight equivalent Al(2)Ba4Ge4 tetrahedra, corners with eight equivalent Al(1)Ba5Ge4 tetrahedra, edges with two equivalent Al(1)Ba5Ge4 tetrahedra, faces with four equivalent Al(1)Ba5Ge4 tetrahedra, and faces with six equivalent Al(2)Ba4Ge4 tetrahedra. In the second Al site, Al(2) is bonded to four equivalent Ba(1), one Ge(1), and three equivalent Ge(2) atoms to form distorted AlBa4Ge4 tetrahedra that share corners with six equivalent Al(2)Ba4Ge4 tetrahedra, corners with eight equivalent Al(1)Ba5Ge4 tetrahedra, edges with two equivalent Al(2)Ba4Ge4 tetrahedra, faces with two equivalent Al(2)Ba4Ge4 tetrahedra, and faces with six equivalent Al(1)Ba5Ge4 tetrahedra. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 7-coordinate geometry to three equivalent Ba(1), one Al(2), and three equivalent Al(1) atoms. In the second Ge site, Ge(2) is bonded in a 8-coordinate geometry to four equivalent Ba(1), one Al(1), and three equivalent Al(2) atoms.
BaAl2Ge2 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 16-coordinate geometry to four equivalent Al(2), five equivalent Al(1), three equivalent Ge(1), and four equivalent Ge(2) atoms. There are a spread of Ba(1)-Al(2) bond distances ranging from 3.42-3.88 Å. There are a spread of Ba(1)-Al(1) bond distances ranging from 3.72-3.85 Å. There is one shorter (3.31 Å) and two longer (3.36 Å) Ba(1)-Ge(1) bond lengths. There are two shorter (3.56 Å) and two longer (3.64 Å) Ba(1)-Ge(2) bond lengths. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to five equivalent Ba(1), one Ge(2), and three equivalent Ge(1) atoms to form distorted AlBa5Ge4 tetrahedra that share corners with eight equivalent Al(2)Ba4Ge4 tetrahedra, corners with eight equivalent Al(1)Ba5Ge4 tetrahedra, edges with two equivalent Al(1)Ba5Ge4 tetrahedra, faces with four equivalent Al(1)Ba5Ge4 tetrahedra, and faces with six equivalent Al(2)Ba4Ge4 tetrahedra. The Al(1)-Ge(2) bond length is 2.58 Å. There are two shorter (2.54 Å) and one longer (2.60 Å) Al(1)-Ge(1) bond length. In the second Al site, Al(2) is bonded to four equivalent Ba(1), one Ge(1), and three equivalent Ge(2) atoms to form distorted AlBa4Ge4 tetrahedra that share corners with six equivalent Al(2)Ba4Ge4 tetrahedra, corners with eight equivalent Al(1)Ba5Ge4 tetrahedra, edges with two equivalent Al(2)Ba4Ge4 tetrahedra, faces with two equivalent Al(2)Ba4Ge4 tetrahedra, and faces with six equivalent Al(1)Ba5Ge4 tetrahedra. The Al(2)-Ge(1) bond length is 2.60 Å. All Al(2)-Ge(2) bond lengths are 2.58 Å. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 7-coordinate geometry to three equivalent Ba(1), one Al(2), and three equivalent Al(1) atoms. In the second Ge site, Ge(2) is bonded in a 8-coordinate geometry to four equivalent Ba(1), one Al(1), and three equivalent Al(2) atoms.