The corresponding UV/vis spectral analysis fully supported these finding. The already described multi-maximum absorption reaching beyond 1000 nm of the aggregate is observed before acid addition. After addition of 3 equiv. of TFA the slightly shifted absorption spectrum of dissolved E isomeric PAT 1 is observed instead (Figure right). Acid addition thus serves as light-independent trigger to disassemble the aggregates of PAT 1 leading to a different deaggregated state, namely the dissolved E isomer. Despite presence of TFA and at least partially protonated amines, the electronic decoupling of the aniline from the PAT core chromophore described above renders the latter's absorption rather insensitive to pH changes.