Triclinic form of bis­{di-μ-hydroxidobis[fac-aqua­tribromido­tin(IV)]} hepta­hydrate

The asymmetric unit of the title hydrate, 2[Sn(H(2)O)(2)(OH)(2)Br(6)]·7H(2)O, comprises two [Br(3)(H(2)O)Sn(μ-OH)(2)SnBr(3)(OH(2))] units, but three independent mol­ecules as two of these are disposed about inversion centres, and seven water mol­ecules. In common with the monoclinic polymorph [Howie et al. (2005 ▶). Inorg. Chim. Acta, 358, 3283–3286], each of the dinuclear species features a central Sn(2)O(2) core, distorted octa­hedral Sn atom geometries defined by a Br(3)O(3) donor set, and an anti-disposition of the coordinated water mol­ecules. In the crystal, O(h)—H⋯O(w), O(a)—H⋯O(w), O(w)—H⋯O(w), and O(w)—H⋯Br (h = hydroxyl, a = aqua, w = water) hydrogen-bonding inter­actions generate a three-dimensional network.