Four pyrene-vinyl-tetraphenylethylene based conjugated materials were synthesized and characterized by FT-IR, NMR, and mass spectroscopy. The photophysical (including absorption, fluorescence, and fluorescence lifetime) and aggregation properties in tetrahydrofuran were investigated. The photophysical and aggregation behavior depends on the spacer, substituent, and also the architecture (mono or tetra-branched) of the molecule. The vinyl spacer mono-branched compound is aggregation induced emission (AIE) active (αAIE = ∼6). Vinyl spacer tetra-branched compounds are AIE inactive, but their emitting efficiency is good in both solution (Φfl = 63%) phase and in the aggregated state (Φfl = 43%). Phenylvinyl spacer tetra-branched compounds emit light strongly in solution (Φfl = 92%), but not in the aggregated state (Φfl = 8%). They are shown to be thermally stable and emit light in the green region (500-550 nm). The results of cyclic voltammetry measurements of these materials showed irreversible oxidation waves, and have high HOMO energy levels (-5.66 to -5.53 eV).

Four dibenzo[a, c]phenazine based donor–acceptor tetra branched molecules were synthesized. The optical (including absorption, steady state and time resolved fluorescence) and electrochemical properties of these compounds were investigated. The emitting behavior of these molecules depends on the donor strength of the side‐arms. Tuning of optical properties has been performed by varying side‐arms. Electron deficient 4‐(2‐benzothiazolyl)phenyl side‐arm compound emit light in the blue region. Weak donor (4‐methoxyphenyl substituted) compound shows red shifted emission in green region. With strong donor (thiophene and triphenylamine) substituted compounds exhibits red and orange‐red emission respectively.

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