Proton magnetic resonance in borax

Abstract Proton magnetic resonance spectra of borax have been recorded from −196° C to +46°C. The change in second moment of 11 G 2 between −40°C and room temperature is not due to free rotation of water molecules. It is possibly caused by their large amplitude hindered oscillations. The energy of activation for this motion and a change in second moment of 1·6 ± 0·3 G 2 at +36°C is discussed in relation to proton conductivity of borax.