Three new heteroleptic copper(II) complexes, [(tmen)Cu(dike)H2O]X where tmen = N,N,N',N'-tetramethylethylenediamine, dike = 2-acetylcyclopentanone anion and X= ClO4- (1), Cl- (2) and Br- (3) are prepared and characterized by elemental analyses, molar conductance measurements and IR and UV-Vis spectroscopy techniques. The complex 1 is fairly soluble in various organic solvents and demonstrates d...