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Updated: Dec 25, 2025
10:40
High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
7.9K
High-resolution resonance-enhanced multiphoton photoelectron circular dichroism
Alexander Kastner1, Greta Koumarianou2, Pavle Glodic2
1Universität Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany.
Physical Chemistry Chemical Physics : PCCP
|March 28, 2020
Summary
Photoelectron circular dichroism (PECD) using nanosecond lasers reveals vibrational independence in chiral molecules. This finding enables enantiomer-specific identification in complex mixtures.
Area of Science:
- Physical Chemistry
- Spectroscopy
- Molecular Physics
Background:
- Photoelectron circular dichroism (PECD) is a sensitive technique for chiral molecule analysis in the gas phase.
- Femtosecond lasers in resonance-enhanced multiphoton ionization (REMPI) lack vibrational resolution.
- Nanosecond lasers offer improved vibrational resolution for REMPI spectroscopy.
Purpose of the Study:
- To investigate the influence of vibrational states on PECD using high-resolution REMPI.
- To explore the potential of vibrationally resolved REMPI-PECD for molecular identification.
Main Methods:
- Utilized a tunable, narrow-band nanosecond laser system.
- Measured REMPI-PECD spectra of fenchone through specific vibrational levels of intermediate Rydberg states (3s and 3p).
Main Results:
- Observed that PECD signals were largely independent of the specific vibrational level excited.
- Demonstrated the feasibility of high-resolution REMPI-PECD measurements.
Conclusions:
- Vibrational independence of PECD suggests a robust chiral sensitivity.
- This approach could enable enantiomer-specific detection and identification of molecules within mixtures.
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