Samples of extremely diluted solid solution of Ne in nH(2) were tested
in the regime of step-wise axial extension at temperatures 1.8 - 4.2
K. A clearly manifested plastifying effect of the neon impurity is obs
erved: larger loads were required to obtain the same deformation in th
e crystals with a lower Ne concentration at a fixed temperature. The u
ltimate strength of doped crystals turned out to be much lower than fo
r pure crystals. The reason behind the loss of strength of nH(2) might
be due to a special mechanism of surmounting of crystal barrier by a
dislocation near an impurity, which has the form of a van der Waals co
mplex Ne(H-2)(n).