Ionic-pair effect on the phosphorescence of ionic iridium(III) complexes

Acetate as counterion in ionic phenylpyridine Iridium(III) complexes containing ethylenediamine or picolylamine as ancillary ligands, induced water solubility and one of the highest phosphorescence quantum yields reported to date in water. The influence of the counterion position on the photophysical properties was highlighted.