α-Terthiophene in non-ionic Triton X-100 micelles: biphotonic creation of its radical cation

α-Terthiophene (αT) has been photophysically and photochemically investigated in a non-ionic micellar environment. The distribution of αT amongst micelles is poissonian, this distribution determining its photophysical and photochemical reactivity. Neither ground-state αT, nor its triplet, migrates between micelles while the radical cation does so via the aqueous bulk. From transient absorption measurements, with different laser energies, it is concluded that the creation of the radical αT·+ is biphotonic, contrary to what has been reported for homogeneous solutions.