On a series of Ir(III) complexes with various numbers of fluorine atoms

In this paper, a series of acetylacetonate derived ligands with various numbers of fluorine atoms, as well as their corresponding Ir(III) complexes, are fabricated and studied. We investigate their single crystal structure, thermal stability, electrochemical property and photophysical performance of these Ir(III) complexes in detail. The effect of fluorine substituent effect on these Ir(III) complexes is also investigated. It is found that the introduction of fluorine atoms into acetylacetonate derived ligand has slim effect on emissive energy and absorption character due to the small contribution of acetylacetonate derived ligand to frontier molecular orbitals. But the introduction of fluorine atoms can improve emissive characters and thermal stability of Ir(III) complexes obviously, including spectral blue shift, excited state lifetime decrease and proper thermal stability. On the other hand excess fluorine atoms compromise above parameters on the contrary.