Table. Coordinates of interstitial sites in conventional unit cells of fec and bcc$."$T$"$ and $"$O$"$

denote tetrahedral and octahedral interstitials, respectively. $N_T(N_O)$ is the number of

tetrahedral $($octahedral$)$ interstitials per conventional unit cell; $R_T(R_O)$ is the radius ratio of

tetrahedral $($octahedral$)$ interstitial to atom.