The protonated water dimer is a prototypical system for the study of proton transfer in aqueous solution. We report infrared photodissociation spectra of cooled H+(H2O)(2) [and D+(D2O2] ions, measured between 620 and 1900 wave numbers (cm(-1)). The experiment directly probes the shared proton region of the potential energy surface and reveals three strong bands below 1600 cm(-1) and one at 1740 cm(-1) (for H5O2+). From a comparison to multidimensional quantum calculations, the three lower energy bands were assigned to stretching and bending fundamentals involving the O...H+...O moiety, and the highest energy band was assigned to a terminal water bend. These results highlight the importance of intermode coupling in shared proton systems.
Gas-phase infrared spectrum of the protonated water dimer / Asmis, Kr; Pivonka, Nl; Santambrogio, Gabriele; Brummer, M; Kaposta, C; Neumark, Dm; Woste, L.. - In: SCIENCE. - ISSN 0036-8075. - 299:5611(2003), pp. 1375-1377. [10.1126/science.1081634]
Gas-phase infrared spectrum of the protonated water dimer
SANTAMBROGIO, GABRIELE;
2003
Abstract
The protonated water dimer is a prototypical system for the study of proton transfer in aqueous solution. We report infrared photodissociation spectra of cooled H+(H2O)(2) [and D+(D2O2] ions, measured between 620 and 1900 wave numbers (cm(-1)). The experiment directly probes the shared proton region of the potential energy surface and reveals three strong bands below 1600 cm(-1) and one at 1740 cm(-1) (for H5O2+). From a comparison to multidimensional quantum calculations, the three lower energy bands were assigned to stretching and bending fundamentals involving the O...H+...O moiety, and the highest energy band was assigned to a terminal water bend. These results highlight the importance of intermode coupling in shared proton systems.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
