Multiresonant coherent multidimensional vibrational spectroscopy of aromatic systems: pyridine, a model system
Kathryn M Kornau1, Mark A Rickard, Nathan A Mathew
1Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
The Journal of Physical Chemistry. A
|March 26, 2011
Summary
This study used multiresonant four wave mixing to analyze pyridine's vibrational modes, revealing cross-peak dynamics and the impact of absorption effects on coherent multidimensional spectroscopy (CMDS). The findings advance CMDS applications for typical molecular transitions.
Area of Science:
- Chemical Physics
- Molecular Spectroscopy
Background:
- Coherent multidimensional spectroscopy (CMDS) typically requires transitions with large transition moments.
- Analyzing molecules with weaker transition moments using CMDS presents experimental challenges.
Purpose of the Study:
- To investigate the application of multiresonant four wave mixing for CMDS of aromatic ring modes in pyridine.
- To identify and characterize cross-peaks between vibrational modes.
- To explore the influence of absorption effects on CMDS pathways.
Main Methods:
- Utilized multiresonant four wave mixing techniques.
- Employed pyridine as a model system for aromatic ring modes.
- Increased pyridine concentration to study absorption effects.
Main Results:
- Successfully measured coherent and incoherent dynamics of pyridine's vibrational modes.
- Identified cross-peaks between several vibrational modes.
- Observed that absorption effects interfere with parametric CMDS pathways but not nonparametric pathways.
Conclusions:
- Multiresonant CMDS can be applied to molecules with typical transition moments.
- Understanding the role of absorption effects is crucial for interpreting CMDS data.
- This work expands the applicability of CMDS to a broader range of molecular systems.
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