Inconsistent hydrogen bond-mediated vibrational coupling of amide I
Suranjana Chakrabarty1, Anup Ghosh1
1a, Department of Condensed Matter of Physics and Materials Sciences, S. N. Bose National Centre for Basic Sciences JD Block, Sector-III, Salt Lake City Kolkata - 700 106 India anupg86@gmail.com anup.ghosh@bose.res.in.
RSC Advances
|January 23, 2023
Summary
This study reveals how amide I vibrational coupling with phenolic compounds depends on guest molecule structure. Substitutions on phenol significantly alter vibrational coupling patterns with amide I.
Area of Science:
- Spectroscopy and Computational Chemistry
- Molecular Interactions and Vibrational Dynamics
Background:
- Amide I band is crucial for understanding molecular interactions.
- Phenolic compounds exhibit characteristic C=C vibrational modes.
Purpose of the Study:
- To investigate vibrational coupling between amide I and phenolic derivatives.
- To elucidate the influence of guest molecule structure on this coupling.
Main Methods:
- Infrared spectroscopy was employed to study molecular vibrations.
- Density Functional Theory (DFT) calculations provided theoretical insights.
Main Results:
- Amide I couples with symmetric and asymmetric C=C modes of phenols.
- Para-cresol showed significant coupling for both modes.
- Para-chlorophenol exhibited significant coupling for symmetric but negligible for asymmetric modes.
Conclusions:
- Vibrational coupling is sensitive to the guest molecule's structure and hydrogen bonding.
- Understanding these coupled dynamics is key for analyzing molecular interactions.
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