Study On Synthesis And Photoluminescence Properties Of "Donor-Naphthalene-Donor" Type Molecular Materials

Four symmetrical "Donor-Naphthalene-Donor" type molecular materials: l,4-bis-(4'-N,N-dimethylamono styryl (BDASN), l,4-bis-(4'-N-pyrrolyl styryl ) naphthalene (BPSN), l,4-bis-(4'-N-hydroxyethyl N-methylamino styryl ) naphthalene (BHMSN) and l,4-bis-(9'-N-ethyl carbazolyl vinyl) naphthalene (BECVN) have been newly synthesized and characterized by mass spectra and HNM spectra in this thesis.The thermostability of these four materials are good. Conduct investigation in photoluminescence properties of these four compouns in different solutions have shown:1) The maximum fluorescence wavelength of four molecular materials appeared in green-emssion band. The maximum UV wavelength red-shifted and the absorbance were increased when the concentration of solutions were increased. It has a rapid improvement of fluorescence intensity when the concentration was increased. The results have shown that the maximum fluorescence wavelength of four molecular materials were red-shifted when the polarity of solvents solution were increased.2) Molecular materials containing weak donor was blue-shifted while those containing strong donor were red-shifted in the same solution.3) It was found that four newly "D-Ï€-D" type molecular materials have the same behavior as "D-Ï€-A" type materials in solution. Lippert equation confirmed that the dipole moment of the exited-state were much bigger than that in the ground-state.4) The relative intensity was improved when light-emitting molecular materials in p-cyclodextrim solution. It is interesting to find that the green-emission band in solvent solution has been quenched, meanwhile, the blue-emission band appeared at the present of B-CD, suggesting that molecular materials have sensitive to the micro-circumstance and have potential application for fluorescence probe.