The Frequency of the Third Harmonic O—H Band of Methanol in Various Solvents, and the Hydrogen Bonding of Methanol with Aromatic Hydrocarbons

The absorption spectra of dilute solutions of methanol in several solvents have been observed in the region of the third harmonic of the OH band. In non-polar solvents the OH frequency is shifted from its position in the vapor by an amount proportional to (D - 1)/(2D + 1) where D is the static dielectric constant of the medium. In certain polar chlorinated solvents the frequency shift is less, but in aromatic solvents the large shift is taken as an indication of hydrogen bond formation.