Capturing electron-driven chiral dynamics in UV-excited molecules.

Area of Science:

• Physical Chemistry
• Molecular Dynamics
• Chirality Studies

Background:

• Chiral molecules exist as non-superimposable mirror images (enantiomers) with distinct properties.
• Applications include enantioselective catalysis, light detection/emission, and molecular switches.
• Controlling electron motion on intrinsic timescales is key to manipulating chiral interactions.

Purpose of the Study:

• To demonstrate and map ultrafast, electron-driven chiral dynamics in neutral molecules.
• To investigate coherent electronic motion initiated by ultraviolet excitation.
• To explore attosecond technology's potential for controlling chiral reactivity.

Main Methods:

• Utilized time-resolved photoelectron circular dichroism (TR-PECD) with 2.9 fs temporal resolution.
• Initiated dynamics with ultraviolet (UV) excitation of neutral chiral molecules.
• Employed theoretical calculations to validate experimental findings.

Main Results:

• Observed coherent electronic motion and beatings between Rydberg states in chiral molecules.
• Detected periodic modulations of the chiroptical response on the few-femtosecond timescale.
• Demonstrated a sign inversion of the chiroptical response in under 10 fs.
• Validated that photoinduced chiral currents act as an enantioselective filter for molecular orientation.

Conclusions:

• Attosecond TR-PECD successfully maps ultrafast electron dynamics in neutral chiral molecules.
• Electronic beatings drive femtosecond chiral dynamics and enantioselective orientation.
• This approach opens avenues for investigating ultrafast chiral systems and enantiosensitive charge-directed reactivity.