A new technique offers a sharp picture of an elusive and ephemeral ... During chemical reactions, molecules pass through a transition state — an unstable, high-energy form that immediately ...

the barrier must be steep enough beyond the transition state for recrossing not to occur, effectively. If (i) is not satisfied, for example, for very high force, the motion becomes (partially ...

scientists have directly imaged a photochemical "transition state," a specific configuration of a molecule's atoms determining the chemical outcome, during a ring-opening reaction in the molecule ...