Ni(O5I)2 crystallizes in the monoclinic P2_1/c space group. Ni(1) is bonded in an octahedral geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one Ni(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent I(1) atoms. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ni(1) and one I(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Ni(1) and one I(1) atom. In the fifth O site, O(5) is bonded in a distorted water-like geometry to two equivalent I(1) atoms. I(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms.
Ni(O5I)2 crystallizes in the monoclinic P2_1/c space group. Ni(1) is bonded in an octahedral geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. Both Ni(1)-O(1) bond lengths are 1.84 Å. Both Ni(1)-O(3) bond lengths are 1.84 Å. Both Ni(1)-O(4) bond lengths are 1.88 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one Ni(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent I(1) atoms. There is one shorter (1.85 Å) and one longer (2.57 Å) O(2)-I(1) bond length. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ni(1) and one I(1) atom. The O(3)-I(1) bond length is 2.51 Å. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Ni(1) and one I(1) atom. The O(4)-I(1) bond length is 1.91 Å. In the fifth O site, O(5) is bonded in a distorted water-like geometry to two equivalent I(1) atoms. There is one shorter (1.84 Å) and one longer (2.57 Å) O(5)-I(1) bond length. I(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms.