Joint Space-Time Coherent Vibration Driven Conformational Transitions in a Single Molecule.

Area of Science:

• Surface science
• Physical chemistry
• Molecular dynamics

Background:

• Understanding molecular behavior at surfaces is crucial for catalysis and materials science.
• Observing ultrafast molecular dynamics requires high temporal and spatial resolution.

Purpose of the Study:

• To investigate single-molecule conformational transitions with angstrom-femtosecond resolution.
• To explore the dynamics and environmental influences on molecular state changes.

Main Methods:

• Utilizing a scanning tunneling microscope (STM) coupled with femtosecond laser pulses.
• Irradiating isolated pyrrolidine molecules adsorbed on a Cu(001) surface.

Main Results:

• Achieved joint angstrom-femtosecond resolution for molecular transitions.
• Observed reversible conformational changes in pyrrolidine molecules.
• Found transition rates decay over time, showing oscillations linked to molecular vibrations and sensitive to the molecular environment.

Conclusions:

• Femtosecond laser pulses enable probing of ultrafast molecular dynamics at the single-molecule level.
• Molecular conformational transitions are dynamic processes influenced by intrinsic vibrations and external molecular interactions.
• This technique provides new insights into surface chemistry and molecular manipulation.