The resonance Raman spectrum has been obtained for the electrogenerated dianion of tetracyanoquinodimethane (TCNQ) upon excitation of its lowest energy electronic transition (λmax 330 nm) with a frequency doubled, flashlamppumped, Rhodamine 640 dye laser. For comparison we report the normal Raman spectrum of solid Li2TCNQ.THF. The electron transfer induced frequency shifts for the second reduction step of TCNQ are measured and interpreted using the π-bond order changes determined from SCF-MO-CI and 1NDO/S electronic structure calculations as well as the π-bond length changes determined from a MNDO-SCF-MO calculation. Finally, the TCNQ2- Raman data is used to identify the oxidation state of TCNQ in the coordination complex [Co(acacen)(py)2]2TCNQ.
ASJC Scopus subject areas
- Colloid and Surface Chemistry