Effects of high atom densities on the NMR relaxation times in solidT2and DT

Experimental NMR data on solid ${\mathrm{T}}_2$ and DT are used to study the effects of high-atom densities on the transverse and longitudinal relaxation times. Data for the second moments, the self-diffusion coefficient, and $T_1$ are analyzed and compared to similar measurements in ${\mathrm{H}}_2$, ${\mathrm{D}}_2$, and HD in order to isolate the contributions to these quantities due to atoms. Subtle effects are seen on the second moments but no direct effect is seen on the value of $T_1$ even for atom densities of order ${10}^{20}$ ${\mathrm{cm}}^{\mathrm{-}3}$.