Wydział Chemii

Zofia Mielke

Stéphane Coussan

Krzysztof Mierzwicki

P. Roubin

Magdalena Sałdyka

2006

Journal of Physical Chemistry A

110

4712-4718

10.1021/jp057300t

Naukowa

Angielski

Artykuł

The complex formed between methanol and tetrafluoromethane has been identified in argon and neon matrixes by help of FTIR spectroscopy. Three fundamentals (ν(OH), ν(FCF), and ν(CO)) were observed for the complex isolated in the two matrixes, and the OH stretch was red shifted in a neon matrix and blue shifted in an argon matrix with respect to the corresponding vibration of the methanol monomer. The theoretical studies of the structure and spectral characteristics of the complexes formed between CH₃OH and CF₄ were carried out at the MP2 level of theory with the 6-311+G(2df,2pd) basis set. The calculations resulted in three stationary points from which two (I-1, I-2) corresponded to structures involving the O−H···F hydrogen bond and the third one (I-3) to the non-hydrogen-bonded structure. The topological analysis of the distribution of the charge density (AIM theory) confirmed the existence of the hydrogen bond in I-1, I-2 complexes and indicated weak interaction between the oxygen atom of CH₃OH and three fluorine atoms of CF₄ in the I-3 complex. The comparison of the experimental and theoretical data suggests that in the matrixes only the non-hydrogen-bonded complex I-3 is trapped. The blue/red shift of the complex OH stretching vibration with respect to the corresponding vibration of CH₃OH in argon/neon matrixes is explained by the different sensitivity of the complex and monomer vibrations to matrix material. The ab initio calculations performed for the ternary CH₃OH−CF₄−Ar systems indicated a negligible effect of an argon atom on the binary complex frequencies.

Alcohols, Monomers, Oscillation, Chemical structure, Noncovalent interactions

https://doi.org/10.1021/jp057300t

https://www.acs.org/content/acs/en.html