Electronic energy transfer in the E(0g+)−D(0u+) system of I2 is investigated in an experiment,
where single rovibrational quantum states are prepared, single collision conditions
prevail, and the final states have been determined from dispersed fluorescence. In
I2∗(E)−X (X=Ar, N2, O2) the collisional decay is found to be governed by minimum
energy transfer. With (X=I2) an anomalous behaviour is found for the initially
prepared E, ν=8, J=56 level, which is tentatively ascribed to vibrational excitation of
the collision partner.