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تسجيل مستخدم جديد$beta$ NMR study of Isolated $^8$Li in the enhanced paramagnet Platinum
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We report {beta} detected nuclear magnetic resonance ({beta}NMR) measurements of 8Li+ implanted into high purity Pt. The frequency of the 8Li {beta}NMR resonance and the spin-lattice relaxation rates 1/T1 were measured at temperatures ranging from 3 to 300 K. Remarkably, both the spin-lattice relaxation rate and the Knight shift K depend linearly on temperature T although the bulk susceptibility does not. K is found to scale with the Curie-Weiss dependence of the Pt susceptibility extrapolated to low temperatures. This is attributed to a defect response of the enhanced paramagnetism of Pt, i.e. the presence of the interstitial Li+ locally relieves the tendency for the Curie-Weiss susceptibility to saturate at low T . We propose that the low temperature saturation in c{hi} of Pt may be related to an interband coupling between the s and d bands that is disrupted locally by the presence of the Li+.
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