Investigation of [CHCl3-CH3OH] complex using matrix-isolation IR spectroscopy and quantum chemical calculation: Evidence of hydrogen- and halogen-bonding interaction

• Published in: Chemical physics 2022-03, Vol.555, p.111451, Article 111451
• Main Authors: Pal, Dhritabrata, Chakraborty, Amrita, Chakraborty, Shamik
• Format: Article
• Language: English
• Subjects: Chloroform; Halogen bond; Hydrogen bond; Infrared; Matrix-isolation; Methanol
• ISSN: 0301-0104
• DOI: 10.1016/j.chemphys.2022.111451

[Display omitted] •First molecular level investigation of [CHCl3-CH3OH] complex using Matrix isolation FTIR.•Dimers are characterised by C-H—O, O-H—Cl hydrogen bond and C-Cl—O halogen bond.•First experimental evidence of formation of halogen bond in CHCl3.•C-H—O hydrogen bonded complex is also identified in the low temperature matrix.•Structure, relative stability, and nature of interactions are calculated. Mixture of CHCl3-CH3OH is a popular non-aqueous solvent mixture that exhibits strong synergistic solvation. The specific interaction between the CHCl3 and CH3OH is investigated using 1:1 complex in N2 matrix along with electronic structure calculation. Three different type of interactions are possible between CHCl3 and CH3OH at the molecular level: C-H···O hydrogen bond, O-H···Cl hydrogen bond, and C-Cl···O halogen bond. One C-H···O hydrogen bond minimum, two O-H···Cl hydrogen bond minima, and one C-Cl···O halogen bond minimum are obtained on the [CHCl3-CH3OH] dimer potential energy surface. Formation of C-H···O hydrogen bonded and C-Cl···O halogen bonded 1:1 complex of [CHCl3-CH3OH] in N2 matrix is confirmed using experimental and simulated IR spectra. The outcome of the current work would help to explain the specific interactions present in CHCl3 and CH3OH binary solvent mixture and to estimate the responses of such non-aqueous solvent mixture.