Variant coordination sphere, for efficient photo- and electroluminescence of 0.4-1.8 μm, of lanthanide(III) complexes containing a β-diketone ligand with low vibrational frequency C-F bonds and a flexible 2,2′-bipyridine ligand

Lanthanide tris(β-diketonate) complexes of variant coordination numbers, [La(hfaa)3(bpy)2], {[Ln(hfaa)3(bpy)(H2O)]·nbpy} (Ln = Nd/Sm, n = 0.5/1) and {[Ln(hfaa)3(bpy)] (Ln = Nd-Yb)} have been synthesized and characterized by elemental analysis, IR, ESI-MS+, 4f-4f absorption, NMR and X-ray crystallography. These volatile and luminescent complexes were used to fabricate OLEDs and the results indicate a highly improved electroluminescence performance over the devices reported in the literature.