NMR Line Broadening in Solids by Slowing Down of Spin Fluctuations
نویسنده
چکیده
The 1°gAg nuclear magnetic resonance line in a sample of polycrystalline AgF is observed to broaden substantially when the 19F spins are irradiated near the magic angle in their rotating frame. This is due to the reduction of 19F-19 F dipolar coupling, which normally causes fluctuations in the 19F-l°9Ag interactions (Abragam and Winter), inducing an exchange narrowing analogous to classical motional narrowing. The l°9Ag linewidths obtained over the entire motional range at different 19F frequencies are compared with those calculated exactly from the ratio of second to fourth moment.
منابع مشابه
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