Criteria for multiexponential relaxation of exchanging nuclei

作者: Uzi Eliav , Gil Navon

DOI: 10.1016/0022-2364(90)90180-H

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摘要: Abstract The validity of the analytical expressions to problem NMR relaxation spin - 3 2 nuclei, based on second-order perturbation theory, is examined by comparison numerical solution Lionville equation. It shown that for a slowly rotating site, although may be well fitted biexponential decay, theory does not give correct values decay rates unless κ ⩽ 1, with = ( χ ω 0 ) 6ω τ R , in which X and TR are quadrupole interaction reorientation time, respectively. above criterion also spins exchange between slow fast sites. Relaxation processes times longer than considered. Analytical given longitudinal system exchanging sites at any concentration ratio.

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