Conformational equilibria in adducts of alcohols with ethers: the rotational spectrum of ethylalcohol-dimethylether
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Updated: May 31, 2026
Interfacial Molecular-level Structures of Polymers and Biomacromolecules Revealed via Sum Frequency Generation Vibrational Spectroscopy
Published on: August 13, 2019
Luca Evangelisti1, Gang Feng, Roberto Rizzato
1Department of Chemistry, University of Bologna, Via Selmi 2, 40126, Bologna, Italy.
Abstract:
The rotational spectra of two conformers of the molecular complex ethylalcohol-dimethylether were measured with pulsed-jet Fourier transform microwave spectroscopy. Both trans and gauche conformations of ethylalcohol are preserved in the complex, originating two conformations with dimethylether as the proton accepting unit. A switch of the conformational stability of ethyl alcohol is observed upon complexation with dimethyl ether, with the gauche form becoming the global minimum. The investigation of the O-D deuterated species allowed observing quantitatively the Ubbelohde effect, which is the shrinkage of the O⋅⋅⋅O distance of about 6 mÅ upon H→D isotopic substitution of the hydroxylic hydrogen participating in the O-H⋅⋅⋅O hydrogen bond.
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