Epitaxial Growth of Thiophene/p-Phenylene Co-oligomers for Highly Polarized Light-Emitting Crystals

Polarized photoluminescence in orientated thin films of π-conjugated oligomers is demonstrated here. Vapor-deposited thiophene/p-phenylene co-oligomers are described and it is shown that these molecules form epitaxial needle-like crystals (see Figure). Molecular modification of the co-oligomers enables the emission color to be tuned and the epitaxial crystallization to be controlled, thus leading to polarized emissions of light.