Provided are organoiridium compounds that are useful as emitters in OLEDs. The compounds have Formula I L1L2Ir-L-Ir-L3L4, where: L is a bis-bidentate ligand including two or more aromatic rings; one of the two or more aromatic rings is bonded to the two Ir atoms at the same time; and each of L1, L2, L3, and L4 is independently a bidentate N-heterocyclic carbene ligand or a substituted or unsubstituted acetylacetonate ligand with L1, L2, L3, and L4 each being the same or different. Also provided are formulations including these organoiridium compounds. Further provided are OLEDs and related consumer products that utilize these organoiridium compounds.