A series of square planar mononuclear palladium (II) complexes,[Pd (L n)(OMe) 2](where L n= 4-(4-chlorophenyl)-6-phenyl-2, 2′-bipyridine, 4, 6-bis (4-chlorophenyl)-2, 2′-bipyridine, 4-(4-bromophenyl)-6-(4-chlorophenyl)-2, 2′-bipyridine, and 6-(4-chlorophenyl)-4-p-tolyl-2, 2′-bipyridine), have been synthesized and characterized. Interaction of palladium complexes with DNA has been investigated by electronic absorption spectra, viscosity ...