Photophysical properties of arylcarbonitrile derivatives: Synthesis, absorption and emission spectra, and quantum chemical studies

A new series of aromatic cyanovinyl compounds were synthesized via one-pot reactions of tri- or tetracyanoethylenes with nucleophilic reagents. The ground-state geometries and UV–vis absorption spectra of the compounds were computationally analyzed by means of density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations, respectively. None of the compounds were fluorescent in solution, but some showed intense emission in the solid state. The first excited singlet states (S1) potential energy surfaces (PESs) were explored using complete active space SCF (CASSCF) calculations for the compounds in order to elucidate nonradiative decay mechanism that takes into account the involvement of conical intersections (CI).

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► Synthesis of new arylcarbonitriles.
► Electronic and emission spectra of the new compounds in solution and solid state.
► Quantum chemistry analysis (TDDFT) for the electronic spectra.
► Quantum chemistry analysis (CASSCF) of conical intersections.