Infrared spectra of homogeneous and heterogeneous proton-bound dimers in the gas phase - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Physical Chemistry Chemical Physics Année : 2005

Infrared spectra of homogeneous and heterogeneous proton-bound dimers in the gas phase

Résumé

Infrared multiphoton dissociation spectra of three homogeneous and two heterogeneous proton-bound dimers were recorded in the gas phase. Comparison of the experimental infrared spectra recorded in the fingerprint region of the proton-bound dimers with spectra predicted by electronic structure calculations shows that all modes which are observed contain motion of the proton oscillating between the two monomers. The O-H-O asymmetric stretch for the homogeneous dimers is shown to occur at around 800 cm-1. As expected, the O-H-O asymmetric stretching modes for the heterogeneous proton-bound dimers are observed to shift to significantly higher energy with respect to those for the homogeneous proton-bound dimers due to the asymmetry of the O-H-O moeity. This shift is shown to be predictable from the difference in proton affinities between the two monomers. Density functional predictions of the infrared spectra based on the harmonic oscillator model are demonstrated to predict the observed spectra of the homogeneous proton-bound dimers with reasonable accuracy. Calculations of the structure and infrared spectrum of protonated diglyme at the B3LYP/6-31+G** level and basis also agree well with an infrared spectrum recorded previously. For both heterogeneous proton-bound dimers, however, the predicted spectra are blue-shifted with respect to experiment.

Dates et versions

hal-00124677 , version 1 (15-01-2007)

Identifiants

Citer

T.D. Fridgen, L. Macaleese, Philippe Maıtre, Terrance B. Mcmahon, Pierre Boissel, et al.. Infrared spectra of homogeneous and heterogeneous proton-bound dimers in the gas phase. Physical Chemistry Chemical Physics, 2005, 7 (14), pp.2747-2755. ⟨10.1039/b504926a⟩. ⟨hal-00124677⟩
66 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More