These observations are consistent with a highly constrained reaction pathway where only a small fraction of incident molecules can cross the dissociation barrier. For obtaining deeper insights into the dissociation dynamics it will be interesting to look into the dissociation process with state-selective preparation of incident CO 2 , as demonstrated recently. 40 This will help in understanding the role of vibration excitation and possibly the effect of alignment of the incident CO 2 on the S 0 , shedding more light on the configurations that are more favorable for barrier crossing.