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An "inverse" harpoon mechanism.

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Area of Science:

  • Physical Chemistry
  • Chemical Physics
  • Quantum Mechanics

Background:

  • Electron transfer reactions are fundamental in chemistry and biology.
  • The quantum nature of electrons enables long-distance transfer.
  • The conventional harpoon mechanism involves Coulombic attraction, accelerating reactions.

Purpose of the Study:

  • To investigate a novel electron transfer mechanism.
  • To explore electron transfer from neutral reactants to multiply charged cations.
  • To characterize the "inverse" harpoon mechanism and its dynamics.

Main Methods:

  • Utilizing nonadiabatic molecular dynamics simulations.
  • Employing three-dimensional coincidence imaging.
  • Initiating dynamics via single-photon double ionization with ultrafast extreme ultraviolet pulses.

Main Results:

  • Observed an "inverse" harpoon mechanism involving repulsion.
  • Electron transfer distance is encoded in kinetic energy release.
  • Simulations predicted and experiments identified "inverse" harpoon products between H2 and HCOH2+.

Conclusions:

  • The study reveals a new repulsive electron transfer pathway.
  • Experimental and theoretical data show good agreement on transfer probability.
  • Theory tends to overestimate the electron transfer distance in this mechanism.