%0 Journal Article
%A Loru, Donatella
%A Steber, Amanda
%A Perez Cuadrado, Cristobal
%A Obenchain, Daniel
%A Temelso, Berhane
%A Lopez, Juan Carlos
%A Schnell, Melanie
%T Quantum tunnelling facilitates the water motion across the surface of phenanthrene
%J Journal of the American Chemical Society
%V 145
%N 31
%@ 0002-7863
%C Washington, DC
%I ACS Publications
%M PUBDB-2022-04965
%P 17201 - 17210
%D 2023
%X Quantum tunnelling is a fundamental phenomenon that plays a pivotal role in the motion and interaction of atoms and molecules. In particular, its influence in the interaction between water molecules and carbon surfaces can have significant implications for a multitude of fields ranging from atmospheric chemistry to separation technologies. Here, we unveil at the molecular level the complex motion dynamics of a single water molecule on the planar surface of the polycyclic aromatic hydrocarbon phenanthrene, which was used as a small-scale carbon surface-like model. In this system, the water molecule interacts with the substrate through weak O-H ...π hydrogen bonds, in which phenanthrene acts as the hydrogen bond acceptor via the high electron density of its aromatic cloud. The rotational spectrum, which was recorded using chirped-pulse Fourier transform microwave spectroscopy, exhibits characteristic line splittings as dynamical features. The nature of the internal dynamics was elucidated in great detail with the investigation of the isotope-substitution effect on the line splittings in the rotational spectra of the H<sub>2</sub><sup>18</sup>O, D<sub>2</sub>O and HDO isotopologues of the phenanthrene-H<sub>2</sub>O complex. The spectral analysis revealed a complex internal dynamic showing a concerted tunnelling motion of the water involving its internal rotation and its translation between the two equivalent peripheral rings of phenanthrene. This high-resolution spectroscopy study presents the observation of a tunnelling motion exhibited by the water monomer when interacting with a planar carbon surface with an unprecedented level of detail. This can serve as a small-scale analogue for water motions on large aromatic surfaces, i.e., large polycyclic-aromatic hydrocarbons and graphene.
%F PUB:(DE-HGF)16
%9 Journal Article
%$ 37494139
%U <Go to ISI:>//WOS:001036869800001
%R 10.1021/jacs.3c04281
%U https://bib-pubdb1.desy.de/record/482830