Rb2ZnI4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one I(1), one I(2), and four equivalent I(3) atoms. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to one I(1), three equivalent I(2), and four equivalent I(3) atoms. Zn(1) is bonded in a tetrahedral geometry to one I(1), one I(2), and two equivalent I(3) atoms. There are three inequivalent I sites. In the first I site, I(1) is bonded in a 1-coordinate geometry to one Rb(1), one Rb(2), and one Zn(1) atom. In the second I site, I(2) is bonded in a 5-coordinate geometry to one Rb(1), three equivalent Rb(2), and one Zn(1) atom. In the third I site, I(3) is bonded to two equivalent Rb(1), two equivalent Rb(2), and one Zn(1) atom to form a mixture of distorted edge, face, and corner-sharing IRb4Zn square pyramids.
Rb2ZnI4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one I(1), one I(2), and four equivalent I(3) atoms. The Rb(1)-I(1) bond length is 3.77 Å. The Rb(1)-I(2) bond length is 3.63 Å. There are two shorter (3.74 Å) and two longer (3.82 Å) Rb(1)-I(3) bond lengths. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to one I(1), three equivalent I(2), and four equivalent I(3) atoms. The Rb(2)-I(1) bond length is 3.83 Å. There is one shorter (3.76 Å) and two longer (4.22 Å) Rb(2)-I(2) bond lengths. There are two shorter (3.78 Å) and two longer (3.80 Å) Rb(2)-I(3) bond lengths. Zn(1) is bonded in a tetrahedral geometry to one I(1), one I(2), and two equivalent I(3) atoms. The Zn(1)-I(1) bond length is 2.63 Å. The Zn(1)-I(2) bond length is 2.61 Å. Both Zn(1)-I(3) bond lengths are 2.62 Å. There are three inequivalent I sites. In the first I site, I(1) is bonded in a 1-coordinate geometry to one Rb(1), one Rb(2), and one Zn(1) atom. In the second I site, I(2) is bonded in a 5-coordinate geometry to one Rb(1), three equivalent Rb(2), and one Zn(1) atom. In the third I site, I(3) is bonded to two equivalent Rb(1), two equivalent Rb(2), and one Zn(1) atom to form a mixture of distorted edge, face, and corner-sharing IRb4Zn square pyramids.