Premium
Simulated infrared spectra of triflic acid during proton dissociation
Author(s) -
Laflamme Patrick,
Beaudoin Alexandre,
Chapaton Thomas,
Spino Claude,
Soldera Armand
Publication year - 2012
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/jcc.22950
Subject(s) - triflic acid , infrared , dissociation (chemistry) , infrared spectroscopy , chemistry , sulfonic acid , nafion , molecule , proton , spectral line , density functional theory , computational chemistry , organic chemistry , catalysis , physics , optics , electrode , quantum mechanics , astronomy , electrochemistry
Abstract Vibrational analysis of triflic acid (TfOH) at different water uptakes was conducted. This molecule mimics the sulfonate end of the Nafion ® side‐chain. As the proton leaves the sulfonic acid group, structural changes within the Nafion ® side‐chain take place. They are revealed by signal shifts in the infrared spectrum. Molecular modeling is used to follow structural modifications that occur during proton dissociation. To confirm the accuracy of the proposed structures, infrared spectra were computed via quantum chemical modeling based on density functional theory. The requirement to use additional diffuse functions in the basis set is discussed. Comparison between simulated infrared spectra of 1 and 2 acid molecules with different water contents and experimental data was performed. An accurate description of infrared spectra for systems containing 2 TfOH was obtained. © 2012 Wiley Periodicals, Inc.