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Inhomogeneous dynamics in confined water nanodroplets.

ABSTRACT: The effect of confinement on the dynamical properties of liquid water was studied by mid-infrared ultrafast pump-probe spectroscopy on HDO:D2O in reverse micelles. By preparing water-containing reverse micelles of different well defined sizes, we varied the degree of geometric confinement in water nanodroplets with radii ranging from 0.2 to 4.5 nm. We find that water molecules located near the interface confining the droplet exhibit slower vibrational energy relaxation and have a different spectral absorption than those located in the droplet core. As a result, we can measure the orientational dynamics of these different types of water with high selectivity. We observe that the water molecules in the core show similar orientational dynamics as bulk water and that the water layer solvating the interface is highly immobile.

SUBMITTER: Dokter AM

PROVIDER: S-EPMC1592463 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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Inhomogeneous dynamics in confined water nanodroplets.

Dokter Adriaan M AM Woutersen Sander S Bakker Huib J HJ

Proceedings of the National Academy of Sciences of the United States of America 20061006 42

The effect of confinement on the dynamical properties of liquid water was studied by mid-infrared ultrafast pump-probe spectroscopy on HDO:D2O in reverse micelles. By preparing water-containing reverse micelles of different well defined sizes, we varied the degree of geometric confinement in water nanodroplets with radii ranging from 0.2 to 4.5 nm. We find that water molecules located near the interface confining the droplet exhibit slower vibrational energy relaxation and have a different spect ...[more]

PMID: 17028175

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