RISC rate constants, kRISC, were calculated for both emitters, which are 2.85 × 10 3 s -1 and 3.04 × 10 3 s - 1 , respectively for DiKTa-OBuIm and DiKTa-DPA-OBuIm, compared to that of DiKTa (4.6 × 10 4 s - 1 ) in toluene. Light-Emitting Electrochemical Cells LEECs were fabricated using DiKTa-OBuIm and DiKTa-DPA-OBuIm as emitters. The device stack was the following: ITO/PEDOT:PSS/emitter/Al (where ITO is indium tin oxide; PEDOT:PSS is poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)). The PEDOT:PSS and the emitter layers were prepared from solution and the device was finished with an evaporated Al top contact. Details of the LEEC fabrication can be found in the General Methods section of the Supporting Information.