The infrared study of fluoroform + methyl fluoride mixtures in argon and nitrogen matrices. Evidence of nonlinear blue-shifting complex formation
Abstract
The FTIR spectra of fluoroform + methyl fluoride mixtures trapped in argon and nitrogen matrices are studied at T 10-30 K. Spectroscopic changes observed in the region of the CH stretching mode of fluoroform are typical for weak blue shifting H - bonds of Csbnd H⋯F type. The degeneracy lifting effect found on E - type bands of fluoroform interacted with methyl fluoride suggests the complex formation of a nonlinear form. The experimental results are confirmed by ab initio calculations of fluoroform + methyl fluoride based on the second order Møller-Plesset theory of perturbations utilizing advanced basis set. Nonlinear complexes are stabilized by the basic Csbnd H⋯F interaction and additionally by van der Waals-type Csbnd D⋯Fsbnd C contacts between deuterated methyl fluoride and fluoroform.
- Publication:
-
Spectrochimica Acta Part A: Molecular Spectroscopy
- Pub Date:
- October 2018
- DOI:
- 10.1016/j.saa.2018.05.105
- Bibcode:
- 2018AcSpA.203..185A
- Keywords:
-
- FTIR spectra;
- Fluoroform;
- Methyl fluoride;
- Ar and N<SUB>2</SUB> matrices;
- Self-associates;
- Blue-shifting H - bond;
- Ab initio calculations;
- AIM