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The Ir centre in the title complex, [Ir(C11H6F2N)2(C6H4NO2)], is six-coordinated in a slightly distorted octa­hedral IrC2N3O fashion.

A series of phosphorescent cyclometalated iridium complexes with 2,5-diphenylpyridine-based ligands has been synthesized and characterized to investigate the effect of the simple ligand modification on photophysics, thermostability and electrochemistry. The complexes have the general structure (C ∧ N) 2 Ir(acac), where C ∧ N is a monoanionic cyclometalating ligand [e.g. 2,5-diphenylpyridyl (dppy), 2,5-di(4-methoxyphenyl)pyridyl (dmoppy), 2,5-di(4-ethoxyphenyl)pyridyl (deoppy) and 2,5-di(4-ethylphenyl)pyridyl (deppy)]. The absorption, emission, cyclic voltammetry and thermostability of the complexes were systematically investigated. The (dppy) 2 Ir(acac) has been characterized using X-ray crystallography. Calculation on the electronic ground state of (dppy) 2 Ir(acac) was carried out using B3LYP density functional theory. The highest occupied molecular orbital (HOMO) level is a mixture of Ir and ligand orbitals, while the lowest occupied molecular orbital (LUMO) is predominantly dppy ligand-based. Electrochemical studies showed the oxidation potentials of (dmoppy) 2 Ir(acac), (deoppy) 2 Ir(acac), (deppy) 2 Ir(acac) were smaller than that of (ppy) 2 Ir(acac), while the oxidation potential of (dppy) 2 Ir(acac) was larger relative to (ppy) 2 Ir(acac). The 10% weight reduction temperatures of these complexes were above that of (ppy) 2 Ir(acac). All complexes exhibited intense green photoluminescence, which has been attributed to MLCT triplet emission. The maximum emission wavelengths in CH 2 Cl 2 at room temperature were in the range 531-544 nm, which is more red-shifted than that of (ppy) 2 Ir(acac).