Emissive Iridium(III) Complexes with Phosphorous-Containing Ancillary

Ir(III) metal complexes and related emitters bearing all kind of cyclometalated chromophoric chelates and non-chromophoric ancillary are extensively studied during the past three decades. Many of them have been found to display bright room temperature phosphorescence from triplet excited states in both solution and solid states, offering a possible application in contemporary optoelectronic technologies, including organic light emitting diodes, electrochemiluminescence, biological imaging and chemical sensing. Among reported materials, there are Ir(III) complexes with at least one phosphorus (P)-containing ligand and/or ancillary chelate, together with cyclometalates or equivalents that are in control of the actual emission energy. Particularly, possession of P-based donor can lead to divergent structural and photophysical properties compared to the traditional designs. This review aims to provide a literature overview as well as the authors' personal account to the development of relevant Ir(III) based phosphors bearing these P-donors. To the readers' convenience, the contents are subdivided into six sessions, according to whether or not they are charge natural, or with mono- or dianionic electronic character, and in accordance to their divergent bonding modes, i. e. monodentate, bidentate and tripodal coordination. In many cases, the P-based ancillaries offer an easy accessible route to the formation of efficient sky-blue and true-blue emitters due to their π-accepting property, together with enlarged emission energy gap and destabilized upper lying quenching state.

A theoretical study on the electronic structures and photophysical properties of phosphorescent Iridium(iii) complexes with –CH3/H and t-Bu substituents

We present the electronic structures, absorption and emission spectra of a series of Ir(iii) complexes to shed light on the effect of different substituents on the photophysical properties.

Spin–orbit coupling analyses of phosphorescent processes in Ir(Zppy)3 (Z = NH2, NO2 and CN)

Appropriate combinations of substituents provide brighter blue-color emission in OLEDs. The present MCSCF + SOCI + SOC calculations suggest that the best material for blue-color emission is fac-Ir(5-NO₂ppy)₃ or fac-Ir(5-NO₂-4,6-dfppy)₃, or practically fac-Ir(5-CN-3,4,6-tfppy)₃.