  Experimental and theoretical studies of fission of doubly-charged Li, Na, and
K clusters in the low fissility regime reveal the strong influence of
electronic shell effects on the fission products. The electronic entropy
controls the quenching of the shell effects and the competition between
magic-fragment channels, leading to a transition from favored channels of
higher mass symmetry to the asymmetric channel involving the trimer cation at
elevated temperatures.
