Femtochemistry: Recent Progress in Studies of Dynamics and Control of Reactions and Their Transition States

This Centennial Issue of The Journal of Physical Chemistry marks not only its achievements since birth in 1896 but also an era of great scientific contributions to the field of chemical dynamics. Pioneering work in the studies of molecular reaction dynamics, which continued over a century, led to new methods of experimentation and to new concepts. Letokhov [1] has identified “three waves” in the development of molecular dynamics, depending on the time scale. In this account we focus on the third wave characterized by femtosecond time resolution. Chemistry occurring on this time scale, femtochemistry, is microscopic, on the length scale of a bond, allowing us to address the nature of transition states and their control, a subject also started in the first part of this century