Energy transfer dynamics of thionin investigated by broad non-resonant holes

Satellite hole spectra of thionin with different concentrations in glycerol:water glass were conducted to study the energy transfer dynamics. Two absorption bands at 603 and 617 nm are assigned to the two forms, amino and imino, of thionin. The absorption band around 570 nm of thionin dimers increases as the thionin concentration increases. Two broad non-resonant holes around 572 and 617 nm are observed when the burning wavelength is tuned to the absorption band of dimers. However, these two broad holes disappear when the burning wavelength is tuned to the low-energy absorption band. The ∼350 cm−1 broad hole-width around 572 nm is predominated by homogeneous broadening. We anticipate that this broad width is predominated by exciton bandwidth. However, the broad hole around 617 nm is produced only when the broad hole around 572 nm appears. We propose that this broad hole is produced via intermolecular energy transfer from the dimers to the monomers.