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Updated: Jul 13, 2026

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Raman jet spectroscopy of formic acid dimers: low frequency vibrational dynamics and beyond
1Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077, Göttingen, Germany.
Abstract:
The vibrational dynamics of formic acid dimer is quite regular at low fundamental excitation frequencies, whereas it evolves into a complex and irregular vibrational signature in the OH stretching region. This is evidenced by the first Raman investigation of the jet-cooled formic acid dimer and its three deuterated isotopomers. Subtle isotope effects in the inter-monomer stretching mode, which is directly observed for the first time at 194 cm(-1), find an interpretation based on hydrogen bond weakening due to quantum delocalization of the protons. The reported high-frequency jet spectra should provide essential experimental stepping stones towards a more complete understanding of this planar prototype for strong double hydrogen bonding.
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