Dramatic effect on lithium-cluster evaporation: The example of Li-11(+)

We have studied the unimolecular evaporation of ionized lithium clusters for different conditions of ionization. In this article we present the total evaporative rates and the monomer-dimer branching ratios for Li-11(+). We observe nonstatistical effects, associated with the dissociation along a less energetically favorable channel. Even after a few microseconds, the internal energy is probably not statistically distributed in all the vibrational modes.