A cryosolution infrared study of the complexes of fluoroform with ammonia and pyridine: Evidence for a C-H...N pseudo blue-shifting hydrogen bond.
Mid-infrared spectra of mixed solutions in liquid xenon containing fluoroform and either ammonia or pyridine have been investigated at temperatures between 173 and 213 K. For both Lewis bases, a new band is found in the CH stretching region at a frequency approximately 5 cm(-1) higher than that of monomer fluoroform, which is assigned to a complex between fluoroform and the Lewis base. A detailed analysis of the nu1/2nu(4) Fermi resonance in the proton donor shows that the blue shifts observed for the complexes are not caused by a strengthening of the CH bond during the complexation, but are due to the changes in the Fermi resonance interactions. Information on the nu1/2nu(4) Fermi resonance was also obtained for the complexes of fluoroform with dimethyl ether and trimethyl amine.
Herrebout
Wouter A
WA
Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020, Antwerp, Belgium.
Melikova
Sonia M
SM
Delanoye
Sofie N
SN
Rutkowski
Konstantin S
KS
Shchepkin
Dimitri N
DN
van der Veken
Benjamin J
BJ
D000641:Ammonia / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D005617:Chlorofluorocarbons, Methane / Q000737:chemistry*; D003116:Color; D006859:Hydrogen / Q000737:chemistry*; D006860:Hydrogen Bonding; D008738:Methyl Ethers / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D012996:Solutions; D013059:Spectrum Analysis, Raman; D014732:Vibration
D005617:Chlorofluorocarbons, Methane; D008738:Methyl Ethers; D011725:Pyridines; D012996:Solutions; D002244:Carbon; D000641:Ammonia; D006859:Hydrogen; C033413:dimethyl ether; D009584:Nitrogen; C023666:pyridine; C009554:fluoroform