Deep red photocatalysis via direct S 0 → T 1 excitation of an Ir( iii ) complex using 740 nm light

(ppy = 2-phenylpyridine; p-biphe = 6,6',7,7'-biphenanthridine). Red light (740 nm) directly excites into the triplet manifold, populating a long-lived excited state (54 ± 3 ns) with mixed triplet metal-to-ligand charge-transfer/ligand-centered character capable of energy-transfer and electron-transfer photocatalysis.