Transient Valence Charge Localization in Strong-Field Dissociative Ionization of HCl Molecules.

Area of Science:

• Atomic and Molecular Physics
• Quantum Chemistry
• Ultrafast Laser Science

Background:

• Advanced light sources enable probing transient phenomena in atomic and molecular inner-shell orbitals.
• Understanding ultrafast charge dynamics is crucial for controlling chemical reactions and molecular processes.

Purpose of the Study:

• To demonstrate asymmetric transient charge localization in the HCl molecule's valence shell during dissociative ionization.
• To visualize ultrafast valence charge motion using intense femtosecond laser pulses.

Main Methods:

• Inducing ultrafast electron tunneling ionization with intense femtosecond laser pulses.
• Analyzing the laser impulse acquired by outgoing ionic fragments.
• Examining the electron tunneling-site distinguished momentum angular distribution of ejected H+ fragments.

Main Results:

• Observed asymmetric transient charge localization in the HCl valence shell during dissociative ionization.
• Encoded transient charge localization within the laser impulse of ionic fragments.
• Revealed asymmetry through detailed analysis of fragment momentum angular distributions.

Conclusions:

• The study visualizes transient valence charge motion in HCl during dissociative ionization.
• Proposes a method to study tunneling-site-sensitive ultrafast dynamics in molecules.
• Stimulates further research into molecular behavior in strong laser fields.