CuInS2 crystallizes in the trigonal R3m space group. Cu(1) is bonded to one In(1), one S(1), and three equivalent S(2) atoms to form distorted CuInS4 tetrahedra that share corners with three equivalent S(1)In3Cu tetrahedra and corners with six equivalent Cu(1)InS4 tetrahedra. In(1) is bonded in a 7-coordinate geometry to one Cu(1), three equivalent S(1), and three equivalent S(2) atoms. There are two inequivalent S sites. In the first S site, S(1) is bonded to one Cu(1) and three equivalent In(1) atoms to form distorted SIn3Cu tetrahedra that share corners with three equivalent Cu(1)InS4 tetrahedra and corners with six equivalent S(1)In3Cu tetrahedra. In the second S site, S(2) is bonded in a 6-coordinate geometry to three equivalent Cu(1) and three equivalent In(1) atoms.
CuInS2 crystallizes in the trigonal R3m space group. Cu(1) is bonded to one In(1), one S(1), and three equivalent S(2) atoms to form distorted CuInS4 tetrahedra that share corners with three equivalent S(1)In3Cu tetrahedra and corners with six equivalent Cu(1)InS4 tetrahedra. The Cu(1)-In(1) bond length is 2.60 Å. The Cu(1)-S(1) bond length is 2.30 Å. All Cu(1)-S(2) bond lengths are 2.37 Å. In(1) is bonded in a 7-coordinate geometry to one Cu(1), three equivalent S(1), and three equivalent S(2) atoms. All In(1)-S(1) bond lengths are 2.57 Å. All In(1)-S(2) bond lengths are 2.88 Å. There are two inequivalent S sites. In the first S site, S(1) is bonded to one Cu(1) and three equivalent In(1) atoms to form distorted SIn3Cu tetrahedra that share corners with three equivalent Cu(1)InS4 tetrahedra and corners with six equivalent S(1)In3Cu tetrahedra. In the second S site, S(2) is bonded in a 6-coordinate geometry to three equivalent Cu(1) and three equivalent In(1) atoms.