Acid-base effects, light emission, DNA-binding and photocleavage studies of oligo-homonuclear ruthenium(II) complexes and their computational study

The mono-, di- and trinuclear ruthenium(II) complexes were observed the ground- and excited state acid ionization constants from the acid-base properties. The DNA binding ability of the complexes increases with increasing π-electron multiplicity of phenanthroline groups and the H-bonding property of imidazole moieties increases from mononuclear to trinuclear complexes as supported by the theoretical studies. Further, these complexes tend to promote cleavage of plasmid DNA under photolytic conditions.