Time-resolved Coulomb explosion imaging: A method to measure structure and dynamics of molecular nuclear wave packets

Coulomb explosion of molecules induced by an intense femtosecond probe laser pulse provides an approach to measure structure and dynamics of internuclear wave packets on a natural spatial (Å) and temporal (fs) scale for molecules. The technique is illustrated by applying it to study photodissociation of ${\mathrm{I}}_2$ initiated by a femtosecond pump pulse. We report a resolution of ∼2–4 Å in the internuclear range ∼7–14 Å using an 80-fs probe pulse. We discuss the ultimate spatial and temporal resolution of the technique, as well as the possibilities of observing dynamics of dissociating polyatomic molecules. Intense femtosecond laser pulses not only provide a way of probing molecular dynamics but they are also an efficient means to initiate dynamics in, e.g., molecular ionic states.