@article {Dunlop2007, title = {8Li in GaAs studied with $\beta$-NMR}, journal = {Physica B}, volume = {401{\textendash}402}, year = {2007}, pages = {254 - 257}, abstract = {β -NMR has been used to study isolated spin polarized Li + 8 in bulk crystalline GaAs. At low temperatures a large fraction (at least 70\%) of the Li end up in locations with cubic symmetry (e.g. a tetrahedral interstitial site). The linewidth of the β -NMR Li + 8 resonance increases dramatically above 150\&$\#$xa0;K, and reaches a maximum at about 290\&$\#$xa0;K. These results are consistent with a site change from an interstitial to a substitutional beginning at ≈ 150 K . The field dependence of the linewidth at 100\&$\#$xa0;K is also discussed.}, issn = {0921-4526}, doi = {http://dx.doi.org/10.1016/j.physb.2007.08.160}, url = {http://www.sciencedirect.com/science/article/pii/S0921452607007077}, author = {T. Dunlop and A.I. Mansour and Z. Salman and K.H. Chow and I. Fan and J. Jung and R.F. Kiefl and S.R. Kreitzman and C.D.P. Levy and W.A. MacFarlane and G.D. Morris and T.J. Parolin} }