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Ultrafast N-H vibrational dynamics of cyclic doubly hydrogen-bonded homo- and heterodimers.

ABSTRACT: Hydrogen-bonded interfaces are essential structural elements in biology. Furthermore, they can mediate electron transport by coupling the electron to proton transfer within the interface. The specific hydrogen-bonding configuration and strength have a large impact on the proton transfer, which exchanges the hydrogen-bonded donor and acceptor species (i.e., NH...O --> N...HO). Modulations of the hydrogen-bonding environment, such as the hydrogen-bond stretch and twist modes, affect the proton-transfer dynamics. Here, we present transient grating and echo peak shift measurements of the NH stretch vibrations of four doubly hydrogen-bonded cyclic dimers in their electronic ground state. The equilibrium vibrational dynamics exhibit strong coherent modulations that we attribute to coupling of the high-frequency NH vibration to the low-frequency interdimer stretch and twist modes and not to interference between multiple Fermi resonances that dominate the substructure of the linear spectra.

SUBMITTER: Petersen PB

PROVIDER: S-EPMC4596713 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Ultrafast N-H vibrational dynamics of cyclic doubly hydrogen-bonded homo- and heterodimers.

Petersen Poul B PB Roberts Sean T ST Ramasesha Krupa K Nocera Daniel G DG Tokmakoff Andrei A

The journal of physical chemistry. B 20080927 42

Hydrogen-bonded interfaces are essential structural elements in biology. Furthermore, they can mediate electron transport by coupling the electron to proton transfer within the interface. The specific hydrogen-bonding configuration and strength have a large impact on the proton transfer, which exchanges the hydrogen-bonded donor and acceptor species (i.e., NH...O --> N...HO). Modulations of the hydrogen-bonding environment, such as the hydrogen-bond stretch and twist modes, affect the proton-tra ...[more]

PMID: 18821789

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Dataset Information

Ultrafast N-H vibrational dynamics of cyclic doubly hydrogen-bonded homo- and heterodimers.

Publications

Ultrafast N-H vibrational dynamics of cyclic doubly hydrogen-bonded homo- and heterodimers.

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