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arXiv · cond-mat/0105350

NMR relaxation rates and Knight shifts in MgB2

Eva Pavarini·I. I. Mazin
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Abstract

We calculate ab initio the NMR relaxation rates and the Knight shifts in MgB_2. We show that the dominant relaxation mechanism at the B nucleus is the interaction with the electronic orbital moment, and we give a simple explanation of that using a simple $sp$ tight binding model. When Stoner enhancement (also calculated ab-initio) is accounted for, we obtain good agreement with reported experimental values. For the 25Mg nucleus, we predict that the dominant relaxation mechanism is the Fermi-contact interaction, which also dominates the Mg Knight shift.

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Eva Pavarini, I. I. Mazin. 2001-05-17. NMR relaxation rates and Knight shifts in MgB2. https://doi.org/10.1103/physrevb.64.140504

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