Ultrafast excited state dynamics of cyclometalated iridium(III) complexes.

Cyclometalated iridium(III) complexes boast photophysical properties that are attractive for a diverse range of applications, including optoelectronic devices, solar fuels, photoredox catalysis, chemical sensing and bioimaging. Radiative emission from the triplet excited state has received significant research attention but what occurs between photon absorption and emission is often taken for granted. In this perspective we provide a comprehensive review of 'ultrafast' excited state dynamics of these versatile phosphors, separated into the main excited state classes of iridium(III) complexes. We aim to provide a foundation of understanding for researchers innovatively applying these organometallic complexes, as well as identify open research questions and current areas of contention in the field.