Pressure Dependence of Hydrogen-Bond Dynamics in Liquid Water Probed by Ultrafast Infrared Spectroscopy
Autori: Lapini A., Pagliai M., Fanetti S., Citroni M., Scandolo S ., Bini R., Righini R.
Affiliazione autori: European Lab Nonlinear Spect, LENS, Via N Carrara 1, I-50019 Florence, Italy; Univ Florence, Dipartimento Chim Ugo Schiff, Via Lastruccia 3, I-50019 Florence, Italy; Abdus Salam Int Ctr Theoret Phys ICTP, I-34151 Trieste, Italy; CNR, INO, Largo Fermi 6, I-50125 Florence, Italy; CNR, Ist Chim Composti Organometallici ICCOM, Via Madonna del Piano 10, I-50019 Sesto Fiorentino, Italy; Scuola Normale Super Pisa, Piazza Cavalieri 7, I-56126 Pisa, Italy
Abstract: Clarifying the structure/dynamics relation of water hydrogen-bond network has been the aim of extensive research over many decades. By joining anvil cell high-pressure technology, femtosecond 2D infrared spectroscopy, and molecular dynamics simulations, we studied, for the first time, the spectral diffusion of the stretching frequency of an HOD impurity in liquid water as a function of pressure. Our experimental and simulation results concordantly demonstrate that the rate of spectral diffusion is almost insensitive to the applied pressure. This behavior is in contrast with the previously reported pressure-induced speed up of the orientational dynamics, which can be rationalized in terms of large angular jumps involving sudden switching between two hydrogen-bonded configurations. The different trend of the spectral diffusion can be, instead, inferred considering that the first solvation shell preserves the tetrahedral structure with pressure and the OD stretching frequency is only slight perturbed.
Giornale/Rivista: THE JOURNAL OF PHYSICAL CHEMISTRY LETTERS
Volume: 7 (18) Da Pagina: 3579 A: 3584
Parole chiavi: MOLECULAR-DYNAMICS; REORIENTATION; MECHANISM; ORDER; OHDOI: 10.1021/acs.jpclett.6b01375Citazioni: 15dati da “WEB OF SCIENCE” (of Thomson Reuters) aggiornati al: 2022-05-22Riferimenti tratti da Isi Web of Knowledge: (solo abbonati) Link per visualizzare la scheda su IsiWeb: Clicca quiLink per visualizzare la citazioni su IsiWeb: Clicca qui