Crystal and molecular structure of aquabis(2,2′-bipyridine)di-µ-hydroxo-sulphatodicopper(II) tetrahydrate

Abstract

The structure of the title compound has been determined from single-crystal three-dimensional X-ray diffractometric data. The structure was solved by the heavy-atom method, and refined by least-squares techniques to R 0·078 for 1962 independent reflections. The copper atoms are bridged by two hydroxo-ligands to give a binuclear species with Cu⋯Cu 2·893(2)Å. Each copper atom has square pyramidal geometry with mean basal Cu–N 2·00 and Cu–O 1·94 Å; the apical Cu–OH₂ is 2·244(5) and Cu–OSO₃ 2·207(5)Å. The dihedral angle between the CuO₂ planes is 6·1 °, and between the basal CuN₂O₂ planes 7·9°. The unco-ordinated water molecules provide a network for hydrogen bonding between the binuclear complexes. The unit cell is monoclinic with Z= 4, a= 9·683 ± 0·01, b= 34·52 ± 0·03, c= 7·822 ± 0·01 Å, β= 103·50 ± 0·05°, space group P2₁/c.