Novel devices containing organic compounds containing electron donor and acceptor characteristics and that act as emissive dopants are provided. The energy ratio obtained by dividing the T1 energy of the emissive dopant by ΔEHOMO-LUMO for the same emissive dopant is at least 0.7 and the first emissive dopant has an energy difference calculated by subtracting the T1 energy of the first emissive dopant from ΔEHOMO-LUMO for the first emissive dopant and the energy difference is at smaller than or equal to 1.00 eV for the novel compounds. The compounds exhibit delayed fluorescence properties when incorporated into OLED devices.