The influence of fragment size and intermediate barriers on competing near-identical simple cleavage reactions: A variational RRKM study

▶ Fragmentation reactions of almost-symmetrical radical cations exhibit remarkable energydependent selectivity, which can be accounted for with variational transition state theory. ▶ Relative rates are not governed by product-like orbiting transition states, but by relatively tight transition states; however, these may not be equally tight. ▶ The transition states for competing cleavage reactions can exhibit energy-dependent shifting.