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Conformational equilibrium and internal dynamics in the iso-propanol-water dimer
Luca Evangelisti1, Qian Gou1, Gang Feng1
1Dipartimento di Chimica "G. Ciamician" dell'Università, Via Selmi 2, I-40126 Bologna, Italy.
Physical Chemistry Chemical Physics : PCCP
|December 6, 2016
Summary
Researchers used microwave spectroscopy to study iso-propanol and water complexes. Two isomers were found, with the inner isomer being more stable and exhibiting tunneling splitting due to internal rotation.
Area of Science:
- Physical Chemistry
- Molecular Spectroscopy
- Supramolecular Chemistry
Background:
- Understanding molecular interactions is key in physical chemistry.
- Iso-propanol-water complexes are relevant in various chemical processes.
Purpose of the Study:
- To investigate the molecular complex between iso-propanol and water.
- To identify and characterize different isomers of the iso-propanol-water adduct.
Main Methods:
- Fourier transform microwave spectroscopy was employed.
- Analysis of rotational spectra to determine molecular structure and properties.
Main Results:
- Two distinct isomers of the iso-propanol-water complex were identified.
- The inner isomer, where water acts as a proton donor to the alcoholic oxygen in a gauche arrangement, is more stable.
- Tunneling splitting of 25.16(8) GHz was observed for the inner isomer, indicating a B2 barrier of approximately 440 cm⁻¹.
Conclusions:
- The study elucidates the structural and energetic properties of iso-propanol-water complexes.
- The findings provide insights into hydrogen bonding and internal dynamics in molecular adducts.
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