Photophysical properties of pyrrolobenzenes with different linking and substitution pattern: The transition between charge transfer states with large (MICT) and small (TICT) resonance interaction

Murali S; Changenet-Barret P; Ley C; Plaza P; Rettig W; Martin MM; Lapouyade R

Chemical Physics Letters, Vol.411, No.1-3, 192-197, 2005

DOI10.1016/j.cplett.2005.06.019 Export Citation

Photophysical properties of pyrrolobenzenes with different linking and substitution pattern: The transition between charge transfer states with large (MICT) and small (TICT) resonance interaction

Murali S, Changenet-Barret P, Ley C, Plaza P, Rettig W, Martin MM, Lapouyade R

Pyrrolobenzenes, with different linking and substitution patterns, 2'-(4-cyanophenyl)-methylpyrrole (MP2-BN) and 2'-(2,5-cyanophenyl)-methylpyrrole (MP2-B25CN), are investigated by steady-state and time-resolved UV-Vis spectroscopy and compared to the parent compound N-pyrrolobenzonitrile (PBN). Both the electron donor-acceptor linking sites and the strength of the electron acceptor moiety are found to influence the emission characteristics of these compounds. The large radiative rate constant of MP2-BN indicates an allowed emission due to mesomeric interaction between the donor and acceptor moieties (MICT), whereas in the case of PBN and MP2-B25CN, the reduced radiative rate constant indicates a forbidden emission from a twisted intramolecular charge transfer (TICT) state. (c) 2005 Elsevier B.V. All rights reserved.