A series of dihydroxy bridged copper(II) complexes of the type [(L)Cu(OH)₂Cu(L)]x₂ * nH₂0, where L is 2,2'-bipyridine, 4,4'-dimethyl-2,2'-bipyridine or 1,10-phenanthroline, x is a counter ion, and n is the number of water molecules, was synthesized. In the case of monohydroxy bridged copper(II) complexes, we have found a new method of synthesis for [ (L)₂Cu(OH)Cu(L)₂ ] (ClO₄)₃, where L is 2,2'-bipyridine or 1,10-phenanthroline. We have synthesized five new monohydroxy bridged copper(II) complexes, thus increasing the number of monohydroxy bridged copper(II) complexes to nine. All complexes have been characterized by infrared spectroscopy, UV-visible spectroscopy, magnetic moments, and elemental analysis. The electron spin resonance results establish that the fulvic acids contain organic free radicals as an internal part of their molecular structure. The concentration of unpaired electrons will increase by increasing the pH. The unpaired electron in fulvic acid interacts with the unpaired electron on copper(II) through the Π system, and this will decrease the spin concentration of fulvic acid complexed with copper(II). The displacement of titration curve from a free ligand (fructose-1,6-diphosphate, ribulose-1,5-diphosphate, phospherine, phosphothreonine, and 3-phosphoglyceric acid, to a ligand plus copper(II) (1:1 ratio) shows there is a strong interaction between copper(II) and the corresponding ligand. All complexes absorb UV-visible at …