A highly emissive bis(phosphine)diarylamido dinuclear copper(I) complex (quantum yield = 57%) was
shown to exhibit E-type delayed fluorescence by variable temp. emission spectroscopy and
photoluminescence decay measurement of doped vapor-deposited films. The lowest energy singlet and triplet
excited states were assigned as charge transfer states on the basis of theor. calcns. and the small obsd. S_1-T_1
energy gap. Vapor deposited OLEDs doped with the complex in the emissive layer gave a max. external
quantum efficiency of 16.1%, demonstrating that triplet excitons can be harvested very efficiently through the
delayed fluorescence channel. The function of the emissive dopant in OLEDs was further probed by several
phys. methods, including elec. detected EPR, cyclic voltammetry, and photoluminescence in the presence of
applied current. Work carried out at Eastman Kodak Company, Rochester, NY 14650, was done prior to Dec.,
2009