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Unveiling Heterogeneity of Interfacial Water through the Water Bending Mode.

ABSTRACT: The water bending mode provides a powerful probe of the microscopic structure of bulk aqueous systems because its frequency and spectral line shape are responsive to the intermolecular interactions. Furthermore, interpreting the bending mode response is straightforward, as the intramolecular vibrational coupling is absent. Nevertheless, bending mode has not been used for probing the interfacial water structure, as it has been yet argued that the signal is dominated by bulk effects. Here, through the sum-frequency generation measurement of the water bending mode at the water/air and water/charged lipid interfaces, we demonstrate that the bending mode signal is dominated not by the bulk but by the interface. Subsequently, we disentangle the hydrogen-bonding of water at the water/air interface using the bending mode frequency distribution and find distinct interfacial hydrogen-bonded structures, which can be directly related to the interfacial organization of water. The bending mode thus provides an excellent probe of aqueous interfacial structure.

SUBMITTER: Seki T

PROVIDER: S-EPMC6844124 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Unveiling Heterogeneity of Interfacial Water through the Water Bending Mode.

Seki Takakazu T Sun Shumei S Zhong Kai K Yu Chun-Chieh CC Machel Kevin K Dreier Lisa B LB Backus Ellen H G EHG Bonn Mischa M Nagata Yuki Y

The journal of physical chemistry letters 20191028 21

The water bending mode provides a powerful probe of the microscopic structure of bulk aqueous systems because its frequency and spectral line shape are responsive to the intermolecular interactions. Furthermore, interpreting the bending mode response is straightforward, as the intramolecular vibrational coupling is absent. Nevertheless, bending mode has not been used for probing the interfacial water structure, as it has been yet argued that the signal is dominated by bulk effects. Here, through ...[more]

PMID: 31647677

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Dataset Information

Unveiling Heterogeneity of Interfacial Water through the Water Bending Mode.

Publications

Unveiling Heterogeneity of Interfacial Water through the Water Bending Mode.

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