[Perspective] Molecular imaging at 1-femtosecond resolution
Thursday, October 20, 2016 - 13:21
in Physics & Chemistry
We cannot yet watch all the steps of a gas-phase chemical reaction as it occurs, but we can come close. On page 308 of this issue, Wolter et al. (1) use an electron-imaging technique to capture the predissociated state of acetylene molecule just 9 fs after its ionization. On this time scale, the departing hydrogen atom and the remaining molecular fragment form an aloof complex in which the electronic coherence required to form bonds between the two is not yet fully lost. Imaging such transient states under different optical excitation conditions with high spatiotemporal resolution holds key information on selective photochemistry that may enable control of chemical reactions. Author: Chong-Yu Ruan