| Based on the results of structure-property relationships of the Dibenzo-suberenyli dene-Ended Fluorophores made by our team, this paper extended the research to Non-benzenoid Aromatic systems. Here are the results:A series ofπ-conjugated compounds, with different ending groups, center cores and different alkoxy chains were successfully synthesized. The structure-property relationship about photoluminescence was discussed in detail. In addition, energy gaps between ground and excited states of these compounds were calculated by semiempirical parametrized PM3 method, which were in good agreement with the experimental observation.We also studied the different fluorescence behavior of these compounds in solutions and in solid states and find that most of the compounds exhibit enhanced emission in solid states, which may arise from restricted rotation, diminished nonradiative routes, etc. Based on Dynamic Light Scattering and Transmission Electron Microscopy measurement of these nano-particles, we find that emission efficiency of nano-suspension is size-dependent, that is, the smaller size the nano particle is, the higher quantum yield it presents.Donor-acceptor conjugated compounds consisted of carbazole and fluorene were synthesized successfully in order to survey the fluorescent phenomena of D-A system. Their photoluminescence properties were investigated in solutions and solid states, respectively. By changing theπ-conjugation linkages, the absorption, fluorescence properties of these compounds is altered. Luminescence in various solvents revealed the intramolecular charge transfer (ICT) process exists in these donor-acceptor (D-A) molecules. From correlation between the Stokes' shifts and solvent polarity parameters, we got the moderate large dipole moments in the excited states. Such push-pull system might be used as sensors for solvent polarity.
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