A combined radioactive tracer and quasielastic neutron scattering study of sodium diffusion in sodium silicate glass

Abstract By means of 22 Na radioactive tracers the Na + tracer diffusion coefficient in the glass Na 2 O·2SiO 2 has been determined in the temperature range of 300 to 400°C. The same sample batch has also been studied by quasielastic neutron scattering using pulsed neutrons of 19.8 A wavelength. From the observed linebroadening at 420°C we derive a Na + self-diffusion coefficient of 3.1×10 −8 cm 2 /s, in excellent agreement with the radioactive tracer results.