We show spectrometrically that H 2 O 2 and HO À solvation resolves the HÀO stretching vibration from the mode of the ordinary water centered at~3200 cm À1 to its below by O:b:O compression. An excessive mode due H 2 O 2 solute appears at3 550 cm À1 and due HO À at~3610 cm À1 , which features the effect of molecular solute bond-order deficiency. The O:b:O compression has the same effect to applied pressure that elongates the solvent HÀO bond and shortens the O:H nonbond. The H 2 O 2 is less than the HO À capable of raising the surface stress and transforming the fraction of the HÀO bonds because of the involvement of solute-solute interactions.[a] J.