Aquadichloro-μ-[3,6-di(2-pyridyl)pyridazine-N,N',N'',N''']-μ-hydroxo-nitrato-O-dicopper(II) dichloro-μ-[3,6-di(2-pyridyl)pyridazine-N,N',N'',N''']mu-hydroxo-mu-nitrato-O,O'-dicopper(II) sesquihydrate, {[Cu2Cl2(OH)(NO3)(C14H10N4)(H2O)][Cu2Cl2(OH)(NO3)(C14H10N4)]}.1.5H2O