catena-Poly[[[[diaquabis[1,2-bis(pyridin-4-yl)diazene]copper(II)]-l-1,2-bis-(pyridin-4-yl)diazene] bis(perchlorate)]]

In the title compound, {[Cu(C10H8N4)3(H2O)2](ClO4)2}n, the coordination environment of the cationic CuII atom isdistorted octahedral, formed by pairs of symmetry- equivalent 1,2-bis(pyridin-4-yl)diazene ligands, bridging 1,2-bis(pyridin-4-yl)diazene ligands and two non-equivalent water molecules. The 1,2-bis(pyridin-4-yl)diazene molecules form polymeric chains parallel to [101] via azo bonds which are situated about inversion centres. Since the CuII atom is situated on a twofold rotation axis, the monomeric unit has point symmetry 2. The perchlorate anions are disordered in a 0.536 (9):0.464 (9) ratio and are acceptors of water H atoms in medium?strong O? H .... O hydrogen bonds with graph set R4 4(12). The watermolecules, which are coordinated to the CuII atom and arehydrogen-bonded to the perchlorate anions, form columnsparallel to [010]. A ? interaction [centroid?centroiddistance = 3.913 (2) A ] occurs between