1.2- Dithioles, intramolecular charge transfer

Excessive five-membered heterocycles with strong 7t-acceptor substituents often display intramolecular charge transfer, which can be of practical significance. Thus, intramolecular charge transfer in the 1,2-dithioles 181 allows a photoinduced color response that is of use in optical filters <1988GEP3636157>. 

MOO 98] Moore A.J., Bryce M.R., Batsanov A.S. et al, New l,3-dithiol-2-ylidene donor-[small pi]-acceptor chromophores with intramolecular charge-transfer properties, and related donor-[small pi]-donor molecules synthesis, electrochemistry. X-ray crystal structures, non-linear optical properties and theoretical calculations , Journal of Materials Chemistry, vol. 8, no. 5, pp. 1173-1184, 1998. 

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