Abstract
The line width (half width) of 17O magnetic resonance and spin-lattice relaxation time, T1, of 17O nucleus were measured for the electrolyte aqueous solution at 298 K by NMR spectroscopy. The values of T1 were independent of pH, but the line width broadened depending on pH as did that of pure water. These half width including the broadening were well estimated from T1 which reflects the rotational mobility of water molecule and the exchange rates of protons depended on pH. The half widths of tap water passed through the commercial purifiers and reformers with the functions such as magnetic field, far infrared radiation by the ceramics, electrolysis, etc. were also calculated from T1 and the exchange rate constants of protons in pure water. Therefore, the half width of water in 17O-NMR suggested by Matsushita can not apply as the factor for a size of water clusters.
