Ultrafast photodissociation of I3− in solution: Direct observation of coherent product vibrations

Abstract
We report the observation of terahertz oscillations in transient transmission measurements following femtosecond UV photolysis of I3 in ethanol solutions. Transmission signals at 620 nm and at 880 nm, which are above and below the λmax of the known absorption of I2 oscillate at precisely opposite phase. This and other results presented indicate that though the oscillations we are observing coherent vibration of the I2 photofragment.