title: Vibrational multilevel quantum coherence due to anharmonic couplings in intermolecular hydrogen bonds.
abstract: Femtosecond three-pulse photon-echo studies of acetic acid dimers in solution reveal multilevel coherence of O-H stretching excitations caused by the anharmonic coupling between the high-frequency stretching and low-frequency hydrogen-bond motions. We demonstrate for the first time that such multilevel coherence determines the nonexponential decay of the macroscopic O-H stretching polarization, whereas spectral diffusion processes play a minor role. The dephasing time of individual vibrational transitions contributing to the overall polarization is approximately 200 fs.
authors: Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2 A, D-12489 Berlin, Germany.
authors: Nils
authors: N
authors: Huse
authors: Karsten
authors: K
authors: Heyne
authors: Jens
authors: J
authors: Dreyer
authors: Erik T J
authors: ET
authors: Nibbering
authors: Thomas
authors: T
authors: Elsaesser