). This phenomenon merits further study, but a conceivable explanation is that more localised charge-transfer complexes with hard conjugate bases are responsible for a larger UV-Vis shift than weaker, more delocalised CT complexes with soft conjugate bases, as observed previously. Previously we discovered, that SNPs are highly fluorescent in benzene suspensions under UVlight irradiation. Here we confirmed the fluorescence of obtained materials in solid state, including newly synthesized frameworks (Figure ). Absolute quantum yields (AQY) measured under 365 nm UV light irradiation vary from 0.3% (at 79.5% absorbance) for SNP-NDT1 to 1.0% (at 79.9% absorbance) for SNP-NDT2 (Table ). We performed solid-state photoluminescence emission (PLE) measurements in steady-state and time-correlated single photon counting (TCSPC) experiments to better understand, how the protonation event influences the optical properties of the materials. As expected, PLE spectra recorded at 440 nm excitation wavelength revealed marked red-shift of the emission maximum after protonation, with emission maxima appearing in the near IR region up to 788 nm for SNP-BDT1 (Figure ). Table . Porous, optical and electronic properties of SNPs.