Syntheses, structures and photoluminescence properties of iridium (III) complexes based on a salen ligand.

The syntheses, structures and photoluminescence properties are reported for two new binuclear cyclometalated iridium(III) complexes, [Ir 2 (ppy) 4 (L)] ( 1 ) and [Ir 2 (F 2 -ppy) 4 (L)] ( 2 ) (ppy=2-phenylpyridine, F 2 -ppy = 2-(2,4-difluorophenyl)pyridine, H 2 L=N,N′-bis(2-hydroxynaphthyl methylidene)-2-hydroxy-1,3-propanediamine. X-ray crystal diffraction shows that L ligands adopt a tetradentate mode to bridge ir(III) ions to form binuclear structures. There are π-π stacking interactions between the binuclear structures, which results in the formation of 3D supramolecular networks. UV–vis absorption spectra and photoluminescence spectra show that the introduction of F − groups in the benzene rings of ppy ligands causes blue shift. [ABSTRACT FROM AUTHOR]