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Revisiting the Linear Relationship between Hydroxyl Stretch Frequency and Bond Length: A Data-Driven Analysis
Sibei Guo1, Jun Jiang1, Hao Ren2
1State Key Laboratory of Precision and Intelligent Chemistry, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui 230026, China.
The Journal of Physical Chemistry Letters
|July 15, 2025
Summary
Computational analysis of carboxylic acids reveals strong correlations between O-H stretching frequency and electrostatic properties. This study clarifies molecular relationships and suggests spectroscopic methods for predicting chemical properties.
Area of Science:
- Computational Chemistry
- Molecular Spectroscopy
- Organic Chemistry
Background:
- The relationship between O-H stretching frequency and hydrogen bond length is a key area in molecular spectroscopy.
- Despite extensive research, a complete understanding of the factors influencing this correlation, particularly in carboxylic acids with intramolecular hydrogen bonds, remains elusive.
Purpose of the Study:
- To computationally investigate the correlation between O-H stretching frequency and bond length in 604 carboxylic acid molecules.
- To identify structural factors, such as ring strain, that influence intramolecular hydrogen bond strength and geometry.
- To establish the relationship between vibrational frequencies and local electrostatic properties.
Main Methods:
- Utilized computational analysis on a dataset of 604 carboxylic acid molecules.
- Categorized molecules based on ring strain to analyze structural influences.
- Correlated vibrational frequencies with electrostatic potential (ESP) extrema.
Main Results:
- Identified significant linear correlations between O-H stretching vibrational frequencies and electrostatic potential (ESP) extrema.
- Demonstrated that ring strain is a key structural factor influencing hydrogen bond strength and geometry in these molecules.
- Established vibrational frequency as a reliable indicator of local electrostatic properties.
Conclusions:
- The study provides a clearer understanding of the fundamental structural relationships governing O-H stretching frequency and hydrogen bond characteristics in carboxylic acids.
- Vibrational frequencies serve as practical proxies for local electrostatic properties, offering insights into molecular interactions.
- Spectroscopic methods can be employed to predict important chemical properties of molecules based on these correlations.
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