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Updated: Aug 25, 2026

Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Tunnelling motion of HF between the two oxygen lone pairs in the dimethyl ether-hydrogen fluoride complex: a pure
Paolo Ottaviani1, Walther Caminati, Biagio Velino
1Dipartimento di Chimica G. Ciamician dell'Università Via Selmi 2, 40126 Bologna, Italy.
Abstract:
The rotational spectrum of the dimethyl ether-hydrogen fluoride complex was assigned by millimetre-wave free-jet absorption spectroscopy. Fine details of the spectrum were resolved by FT microwave molecular-beam spectroscopy. The HF group acts as a proton donor and tunnels at a rate of 44178.2(7) MHz between the two oxygen lone pairs, which corresponds to an inversion barrier of 0.17 (1) kcal mol-1. The barrier to internal rotation of the two methyl groups is about 25% lower relative to the isolated ether.
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