Structure of the triplet excited state of tetrabromo-p-benzoquinone from time-resolved resonance Raman spectra and ab initio calculations

The triplet excited state of bromanil has been observed using time-resolved resonance Raman spectroscopy. Assignments of the bands have been made by comparison with spectra of the ground state and of benzoquinone as well as its fluorinated and chlorinated analogues. The structure in the triplet excited state has been determined using ab initio calculations. The combined experimental and computed results confirm a greater degree of bond reorganization in the triplet of bromanil compared to benzoquinone or fluoranil.