Hydration and Seamless Integration of Hydrogen Peroxide in Water

Raman multivariate curve resolution is used to decompose the vibrational spectra of aqueous hydrogen peroxide (H₂O₂) into pure water, dilute H₂O₂, and concentrated H₂O₂ spectral components. The dilute spectra reveal four sub-bands in the OH stretch region, assigned to the OH stretch and Fermi resonant bend overtone of H₂O₂, and two nonequivalent OH groups on water molecules that donate a hydrogen bond to H₂O₂. At high concentrations, a spectral component resembling pure H₂O₂ emerges. Our results further demonstrate that H₂O₂ perturbs the structure of water significantly less than either methanol or sodium chloride of the same concentration, as evidenced by comparing the hydration-shell spectra of tert-butyl alcohol dissolved in the three aqueous solutions.