Then, Maeda and Kitano are referring about literature on analysis and interpretations of "composite O-H stretching Raman band". Among the early approaches, we can find those that "were carried out by the decomposition of the contour into Gaussian or Lorentzian components." We find again Walrafen, who investigated "pure water in the temperature range 10-95°C, and decomposed the band into four Gaussian components, pairs of which had opposite temperature dependencies, two lower-frequency components (3247, 3435 cm -1 ) decreased in intensity with increasing temperature whilst two higher-frequency components (3535, 3622 cm -1 ) increased in intensity" (Maeda and Kitano mentioning . "They also indicated the existence of an isosbestic point near 3460 cm -1 in the spectra. The isosbestic behavior suggests that two distinct scattering components exist, the simplest probability being scattering from hydrogen-bonded and nonhydrogen-bonded O-H oscillators. Walrafen interpreted the O-H stretching band as due to an equilibrium between the five-molecule, fully hydrogen-bonded structure having intermolecular C2v symmetry, and nonhydrogen-bonded monomeric water" (Maeda and Kitano, mentioning the Walrafen's work). The "isosbestic point" is the "Wavelength, wavenumber or frequency at which the total absorbance of a sample does not change during a chemical reaction or a physical change of the sample." (IUPAC) Maeda and Kitano are also mentioning another interpretation. "Scherer et al. also interpreted the O-H stretching band of water in terms of four Gaussian components, which were attributed to symmetric and antisymmetric O-H stretching vibrations of a symmetrically hydrogen-bonded and an asymmetrically hydrogen-bonded complex. They assumed that water molecules have strong hydrogen bonding on both of their hydrogen atoms in the symmetrically hydrogen-bonded complex, and that each water molecule has one strong and one weak hydrogen bond in the asymmetrically hydrogen-bonded complex" . However, "Georgiev and co-workers pointed out a limitation of the decomposition method because of necessity of making a preliminary assumption concerning the number and the shape of the component, and they applied the method of Fourier deconvolution. They divided the O-H stretching spectra of H2O into four components in the isotropic spectra and three in the anisotropic spectra" .