Аннотация:
The
quasielastic neutron scattering
experiments on liquid sodium (at $T= 378$, $573$, and $693$ K) and
sodium-hydrogen melt ($T = 693\,$K,
hydrogen concentration ${\sim}\,0.4\%$ at.) were performed with the DIN-2PI time-of-
flight spectrometer. The
characteristics of the diffusion mobility for particles comprising the liquids
studied are extracted from the
experimental results and analyzed with the help of the phenomenological and
“relaxing cage” models. The
self-diffusion coefficient in liquid sodium obtained for all temperatures is in
the agreement with the values known
from literature. The diffusion mobility in pure sodium and in sodium–hydrogen
melt were found to be coinciding; it
leads to the conclusion that in our experimental conditions hydrogen exists and
diffuses in melt in the form of hydride
NaH.