Hydrogen-Bond Dynamics of CH⋅⋅⋅O Interactions: The Chloroform⋅⋅⋅Acetone Case

✍ Scribed by Pedro D. Vaz; Mariela M. Nolasco; Francisco P. S. C. Gil; Paulo J. A. Ribeiro-Claro; John Tomkinson

• Book ID: 101837518
• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 452 KB
• Volume: 16
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/chem.201000479

✦ Synopsis

Abstract

Spectroscopic evidence for CH**⋅⋅⋅O hydrogen bonding in chloroform⋅⋅⋅acetone [Cl~3~CH⋅⋅⋅OC(CH~3~)~2~] mixtures was obtained from vibrational inelastic neutron scattering (INS) spectra. Comparison between the INS spectra of pure samples and their binary mixtures reveals the presence of new bands at about 82, 130 and 170 cm^−1^. Assignment of the 82 cm^−1^ band to the νO⋅⋅⋅H anti‐translational mode is considered and discussed. In addition, the βCH mode of CHCl~3~ at 1242 cm^−1^ is split in the spectra of the mixtures, and the high‐wavenumber component is assigned to the hydrogen‐bonded complex. The plot of the integrated intensity of this component shows a maximum for x=0.5, in agreement with the 1:1 stoichiometry of the chloroform⋅⋅⋅**acetone complex, with a calculated complexation constant of 0.15 dm^3^ mol^−1^. Results also show that the complex behaves as an independent entity, that is, despite being weak, such interactions play a key role in supramolecular chemistry.