Filming enhanced ionization in an ultrafast triatomic slingshot

Filming atomic motion within molecules is an active pursuit of molecular physics and quantum chemistry. A promising method is laser-induced Coulomb Explosion Imaging (CEI) where a laser pulse rapidly ionizes many electrons from a molecule, causing the remaining ions to undergo Coulomb repulsion. The ion momenta are used to reconstruct the molecular geometry which is tracked over time (i.e., filmed) by ionizing at an adjustable delay with respect to the start of interatomic motion. Results are distorted, however, by ultrafast motion during the ionizing pulse. We studied this effect in water and filmed the rapid slingshot motion that enhances ionization and distorts CEI results. Our investigation uncovered both the geometry and mechanism of the enhancement which may inform CEI experiments in many other polyatomic molecules.

Automated summary

Filming atomic motion within molecules is an active pursuit of molecular physics and quantum chemistry, and laser-induced Coulomb Explosion Imaging (CEI) is a promising method. However, the rapid motion during ionization distorts the CEI results. Our study on water revealed the rapid slingshot motion that enhances ionization and distorts CEI results, providing insights into the geometry and mechanism of this enhancement, which can inform CEI experiments in other polyatomic molecules.