The peak contributing intensity at around 3250 cm -1 arises as a result of an interplay of the intermolecular coupling of O-H dipoles and the intramolecular coupling of O-H dipoles of the same water molecule, facilitating the Fermi resonance between ν1 and 2ν2. The intramolecular coupling can occur because the two O-H dipoles on the same molecule are connected by the O-atom. On the contrary, the intermolecular coupling can occur because the water molecules are connected by the extensive hydrogen-bonding network. The intermolecular coupling is comparatively stronger than the intramolecular coupling. This was evidenced in a study, through more diminished intensity of this shoulder region in aqueous solutions with less possibility of intermolecular coupling due to introduction of salt ions. Thus, an increased spectral intensity for the 3250 cm -1 peak, indicates a more extensive hydrogen-bonding network while a decrease in its intensity can be associated with disruptions in the hydrogenbonding network, which inevitably leads to diminished coupling probabilities.