Ultrafast Reaction Dynamics

A decade ago this magazine devoted a special issue to laser chemistry (see PHYSICS TODAY, November 1980). One of the articles emphasized the importance of time scales in chemical reactions and the possible use of ultrashort lasser pulses to induce chemistry. Over the past 10 years new laser techniques, and gas‐phase and molecular‐beam experiments, have revealed much about the fundamental steps of elementary chemical reactions. These approaches and the tremendous detail they have exposed about the dynamics of chemical reactions are the subject of the present article. With new laser techniques and with gas phase and molecular beam experiments, it is now possible to determine the ultrafast motion in isolated chemical reactions—chemistry on the 10^(−13)‐second time scale