Al(CoSi)2 crystallizes in the trigonal P-3m1 space group. Co(1) is bonded in a distorted body-centered cubic geometry to three equivalent Al(1) and five equivalent Si(1) atoms. Al(1) is bonded to six equivalent Co(1) and six equivalent Si(1) atoms to form distorted face-sharing AlCo6Si6 cuboctahedra. Si(1) is bonded in a 11-coordinate geometry to five equivalent Co(1), three equivalent Al(1), and three equivalent Si(1) atoms.
Al(CoSi)2 crystallizes in the trigonal P-3m1 space group. Co(1) is bonded in a distorted body-centered cubic geometry to three equivalent Al(1) and five equivalent Si(1) atoms. All Co(1)-Al(1) bond lengths are 2.37 Å. There are a spread of Co(1)-Si(1) bond distances ranging from 2.25-2.40 Å. Al(1) is bonded to six equivalent Co(1) and six equivalent Si(1) atoms to form distorted face-sharing AlCo6Si6 cuboctahedra. All Al(1)-Si(1) bond lengths are 2.76 Å. Si(1) is bonded in a 11-coordinate geometry to five equivalent Co(1), three equivalent Al(1), and three equivalent Si(1) atoms. All Si(1)-Si(1) bond lengths are 2.64 Å.