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Title: High resolution two-dimensional infrared (HR-2DIR) spectroscopy of gas phase molecules
Two-dimensional infrared (2DIR) spectroscopy has become an established method for generating vibrational spectra in condensed phase samples composed of mixtures that yield heavily congested infrared and Raman spectra. These condensed phase 2DIR spectrometers can provide very high temporal resolution (<1 ps), but the spectral resolution is generally insufficient for resolving rotational peaks in gas phase spectra. Conventional (1D) rovibrational spectra of gas phase molecules are often plagued by severe spectral congestion, even when the sample is not a mixture. Spectral congestion can obscure the patterns in rovibrational spectra that are needed to assign peaks in the spectra. A method for generating high resolution 2DIR spectra of gas phase molecules has now been developed and tested using methane as the sample. The 2D rovibrational patterns that are recorded resemble an asterisk with a center position that provides the frequencies of both of the two coupled vibrational levels. The ability to generate easily recognizable 2D rovibrational patterns, regardless of temperature, should make the technique useful for a wide range of applications that are otherwise difficult or impossible when using conventional 1D rovibrational spectroscopy.  more » « less
Award ID(s):
1832098
PAR ID:
10485871
Author(s) / Creator(s):
; ;
Publisher / Repository:
American Institute of Physics (AIP)
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
157
Issue:
18
ISSN:
0021-9606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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