Synthesis, characterization and third-order nonlinear optical properties of a series of ruthenium(II) complexes containing 2-arylimidazo-[4,5-f][1,10]phenanthroline

Three novel mononuclear ruthenium(II) complexes [Ru(dmP)(2)L](2+) [dmp=2,9-dimethyl-1,10-phenanthroline, L = 2-phenylimidazo-[4,5-f][1,10]phenanthroline (PIP), 2-(4'-hydroxyphenyl)imidazo-[4,5-f][1,10]phenanthroline (HOP), 2-(4'-dimethylaminophenyl)imidazo-[4,5-f][1,10]phenanthroline (DMNP)] were synthesized and characterized by ES-MS, H-1 NMR, UV-Vis and electrochemistry. The nonlinear optical (NLO) properties of the ruthenium(II) complexes were investigated by Z-scan techniques with 12 ns laser pulses at 540 nm, and all of them exhibit both NLO absorption and self-defocusing effects. The corresponding effective NLO susceptibility \chi(3)vertical bar of the complexes is in the range of 5.15 x 10(-12) -6.34 x 10(-12) esu.