2008: Identifying the low-lying electronic states of anthracene-9,10-endoperoxide

Corral, I; Gonzalez, L; Lauer, A; Freyer, W; Fidder, H; Heyne, K

CHEMICAL PHYSICS LETTERS 2008, 452(1-3), p. 67-71

The electronic excited states of anthracene-9,10-endoperoxide giving rise to singlet oxygen generation (1O2) or homolytic O-O cleavage have been unambiguously characterized using multi-configurational second order perturbation theory MS-CASPT2/CASSCF, with inclusion of solvent interactions, femtosecond polarization resolved UV/IR pump-probe, and steady-state fluorescence experiments. The S1 state, responsible for homolytic O-O cleavage, is observed at 34400 cm-1. Determination of the transition dipole moment direction of the 37000 cm-1 band, confirms the assignment of the S4 state, from which 1O2 is generated, and allows assigning the other electronic states. Furthermore, it is demonstrated that APO can emit after electronic excitation.

 

DOI 10.1016/j.cplett.2007.12.013