Absorption spectrum of water as a reflection of charge diffusion
The absorption spectrum of liquid water in the range of 103–1013 Hz (from dc conductivity of up to 5 THz IR resonance) is completely and uniformly described by a simple physical model. The model assumes the existence in water of a high concentration of H3O+ and OH− ions (up to 4.5% of the total number of molecules) that exchange protons with H2O molecules on the scale of picoseconds.