ABSTRACT Hydrogen bonding of methanol, and deuterated methanol in carbon tetrachloride was studied by Fourier transform infrared spectroscopy in the range of 2000 to 4000 cm-1 According to the concentration, alcohols self-aggregated to form monomer, dimer, trimer, and tetramer. Each spectrum was resolved, and the formation constants and the band-widths of each species were determined. The resolved spectra were well expressed in Gaussian forms. The ratio of the band-widths (or intensities) between hydrogen bond and deuterium bond was 21/2 (=1.414) as is predicted by the theory. Molecular orbital ab initio calculations were used to calculate the equilibrium geometries and total energies for multimer formation. The observed changes in the bond-length when monomers were polymerized into dimer, trimer, and tetramer, agreed with the ab initio calculations. In this paper, the electrostatic model is introduced in the adiabatic approximation theory of hydrogen bonding. It would be shown that this model could interpret the spectral shifts, intensity changes, bond-length variations and spectral band-width changes of hydrogen-bonded systems.
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