Pump-probe absorption anisotropy of the hydrated electron. A theory

Pump-probe absorption dichroism is studied in the case of the hydrated electron. This theory is a statistical theory using a correlation function description of the nonlinear optical processes involved. Its basic ingredient is the assumption of cascade-type interstate dynamics in the excited p-states of (ermaq−). It is shown that if the latter are fast enough, the pump-probe dichroism disappears in most circumstances; it persists for a zero time delay and coinciding pump and probe frequencies. Cascade relaxation times of the order of 10 fs or less are required for that purpose.