Abstract: Two conjugating electron donor-acceptor(D-A)compounds,2-tricyanovinyl anthracene(2-TCVA)and 9-tricyanovinyl anthracene(9-TCVA),were synthesized and their spectroscopic properties in a series of solvents with different polarity and at different temperature were studied.The results reveal that the structure of 2-TCVA is more planar than 9TCVA at their ground state and the charge transfer bands show up in their absorption spectra.Fluorescence emits from intramolecular charge transfer(ICT)state for 9-TCVA in nonpolar solvents,while for 2-TCVA in both polar and non-polar solvents. When the molecule was freezed,2-TCVA emits fluorescence from its ICT state,while 9-TCVA emits dual fluorescence from its local and ICT state,due to the structure of 2-TCVA is more planar than 9-TCVA. The dipole moment difference between excited state and ground state for 2-TC-VA was estimated as 18.8 D.

Key words: intramolecular charge transfer, charge separation, spiral conjugation