Chirped wavepacket dynamics of HgBr from the photolysis of HgBr2 in solution

Wavepacket dynamics of the HgBr radical produced by the impulsive photodissociation of HgBr2 in solution was investigated using femtosecond absorption spectroscopy. Whereas the photolysis in CH3CN shows conventional damped wavepacket dynamics of HgBr, in dimethyl sulfoxide a chirped wavepacket with a nonexponential decay is observed. The chirp, which is attributed to the modification of the HgBr potential as a result of solvation occurring on the timescale of the wavepacket motion, provides microscopic insight into the structural and dynamical properties of the solvation. The effects on the observed dynamics from the presence of two wavepackets is also considered.