| Abstract
| - The complex formed between methanol and tetrafluoromethane has been identified in argon and neon matrixesby help of FTIR spectroscopy. Three fundamentals (ν(OH), ν(FCF), and ν(CO)) were observed for the complexisolated in the two matrixes, and the OH stretch was red shifted in a neon matrix and blue shifted in an argonmatrix with respect to the corresponding vibration of the methanol monomer. The theoretical studies of thestructure and spectral characteristics of the complexes formed between CH3OH and CF4 were carried out atthe MP2 level of theory with the 6-311+G(2df,2pd) basis set. The calculations resulted in three stationarypoints from which two (I-1, I-2) corresponded to structures involving the O−H···F hydrogen bond and thethird one (I-3) to the non-hydrogen-bonded structure. The topological analysis of the distribution of the chargedensity (AIM theory) confirmed the existence of the hydrogen bond in I-1, I-2 complexes and indicated weakinteraction between the oxygen atom of CH3OH and three fluorine atoms of CF4 in the I-3 complex. Thecomparison 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 thecorresponding vibration of CH3OH in argon/neon matrixes is explained by the different sensitivity of thecomplex and monomer vibrations to matrix material. The ab initio calculations performed for the ternaryCH3OH−CF4−Ar systems indicated a negligible effect of an argon atom on the binary complex frequencies.
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