K2CoI4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one I(1), one I(3), and four equivalent I(2) atoms. In the second K site, K(2) is bonded in a 6-coordinate geometry to one I(1), one I(3), and four equivalent I(2) atoms. Co(1) is bonded in a tetrahedral geometry to one I(1), one I(3), and two equivalent I(2) atoms. There are three inequivalent I sites. In the first I site, I(1) is bonded in a distorted T-shaped geometry to one K(1), one K(2), and one Co(1) atom. In the second I site, I(2) is bonded to two equivalent K(1), two equivalent K(2), and one Co(1) atom to form a mixture of distorted edge, corner, and face-sharing IK4Co square pyramids. In the third I site, I(3) is bonded in a T-shaped geometry to one K(1), one K(2), and one Co(1) atom.
K2CoI4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one I(1), one I(3), and four equivalent I(2) atoms. The K(1)-I(1) bond length is 3.57 Å. The K(1)-I(3) bond length is 3.50 Å. There are two shorter (3.59 Å) and two longer (3.65 Å) K(1)-I(2) bond lengths. In the second K site, K(2) is bonded in a 6-coordinate geometry to one I(1), one I(3), and four equivalent I(2) atoms. The K(2)-I(1) bond length is 3.64 Å. The K(2)-I(3) bond length is 3.58 Å. There are two shorter (3.64 Å) and two longer (3.67 Å) K(2)-I(2) bond lengths. Co(1) is bonded in a tetrahedral geometry to one I(1), one I(3), and two equivalent I(2) atoms. The Co(1)-I(1) bond length is 2.59 Å. The Co(1)-I(3) bond length is 2.59 Å. Both Co(1)-I(2) bond lengths are 2.59 Å. There are three inequivalent I sites. In the first I site, I(1) is bonded in a distorted T-shaped geometry to one K(1), one K(2), and one Co(1) atom. In the second I site, I(2) is bonded to two equivalent K(1), two equivalent K(2), and one Co(1) atom to form a mixture of distorted edge, corner, and face-sharing IK4Co square pyramids. In the third I site, I(3) is bonded in a T-shaped geometry to one K(1), one K(2), and one Co(1) atom.