(K4Re2OCl10)2O2 crystallizes in the tetragonal I4/mmm space group. The structure consists of two water atoms inside a K4Re2OCl10 framework. In the K4Re2OCl10 framework, there are two inequivalent K sites. In the first K site, K(1) is bonded in a body-centered cubic geometry to eight equivalent Cl(1) atoms. In the second K site, K(2) is bonded to four equivalent Cl(2) and eight equivalent Cl(1) atoms to form KCl12 cuboctahedra that share corners with four equivalent K(2)Cl12 cuboctahedra, faces with four equivalent K(2)Cl12 cuboctahedra, and faces with four equivalent Re(1)Cl5O octahedra. Re(1) is bonded to one O(1), one Cl(2), and four equivalent Cl(1) atoms to form ReCl5O octahedra that share  a cornercorner with one Re(1)Cl5O octahedra and faces with four equivalent K(2)Cl12 cuboctahedra. The corner-sharing octahedra are not tilted. O(1) is bonded in a linear geometry to two equivalent Re(1) atoms. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to two equivalent K(1), two equivalent K(2), and one Re(1) atom to form a mixture of distorted corner, face, and edge-sharing ClK4Re square pyramids. In the second Cl site, Cl(2) is bonded in a distorted single-bond geometry to four equivalent K(2) and one Re(1) atom.
(K4Re2OCl10)2O2 crystallizes in the tetragonal I4/mmm space group. The structure consists of two water atoms inside a K4Re2OCl10 framework. In the K4Re2OCl10 framework, there are two inequivalent K sites. In the first K site, K(1) is bonded in a body-centered cubic geometry to eight equivalent Cl(1) atoms. All K(1)-Cl(1) bond lengths are 3.25 Å. In the second K site, K(2) is bonded to four equivalent Cl(2) and eight equivalent Cl(1) atoms to form KCl12 cuboctahedra that share corners with four equivalent K(2)Cl12 cuboctahedra, faces with four equivalent K(2)Cl12 cuboctahedra, and faces with four equivalent Re(1)Cl5O octahedra. All K(2)-Cl(2) bond lengths are 3.61 Å. All K(2)-Cl(1) bond lengths are 3.56 Å. Re(1) is bonded to one O(1), one Cl(2), and four equivalent Cl(1) atoms to form ReCl5O octahedra that share  a cornercorner with one Re(1)Cl5O octahedra and faces with four equivalent K(2)Cl12 cuboctahedra. The corner-sharing octahedra are not tilted. The Re(1)-O(1) bond length is 1.86 Å. The Re(1)-Cl(2) bond length is 2.40 Å. All Re(1)-Cl(1) bond lengths are 2.39 Å. O(1) is bonded in a linear geometry to two equivalent Re(1) atoms. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to two equivalent K(1), two equivalent K(2), and one Re(1) atom to form a mixture of distorted corner, face, and edge-sharing ClK4Re square pyramids. In the second Cl site, Cl(2) is bonded in a distorted single-bond geometry to four equivalent K(2) and one Re(1) atom.