Abstract
A series of bichromophoric molecules (PAP-X-Red), are synthesized. The 3, 5 positions of PAP are modified by substitution groups of different sizes. The additivity of UV spectra of the two chromophores indicates no strong interaction between the chromophores in the ground state. Analysis of the excitation spectra suggests the occurrences of intramolecular energy transfer. According to QM calculation, the orientation between emission and absorption transition dipole of the two choromophores are almost perpendicular, but the energy transfer rate is still large due to the proximity of the two chromophores. In OLED device fabrication, PAP-Isp-Red exhibited good hole transport property, but the low quantum yield make it a poor emitter.