Spin diffusion in solids

Multidimensional and heteronuclear NMR techniques have revolutionised the use of NMR spectroscopy for the structure determination of organic molecules from small to complex. Multidimensional NMR also allows observation of forbidden multiple-quantum transitions and probing of slow dynamic processes, such as chemical exchange, cross-relaxation, transient Over-hauser effects, and spin-diffusion in solids. 

Diffusion edited JH NMR spectroscopy DE Only large molecules, macromolecular domains, and stable aggregates are observed. Often simplifies the ID H as signals from small molecules (including solvents and water) are removed. A very powerful approach that is underutilized. Diffusion editing is relates to molecular selfdiffusion in solution. It should not be confused with spin diffusion in solids, which is completely unrelated. 

An important application of spin diffusion in solid-state NMR is its use as a correlation mechanism in two-dimensional NMR spectra [13, 59]. The description of a two-dimensional tensor-correlation experiment using spin diffusion as a transport mechanism follows the general scheme for two-dimensional experiments (see Fig. 4.1) [7]. During the evolution time (tf), the polarization is labeled with the resonance frequency of spin k (fi ), during... 

B.H. Meier, Polarization transfer and spin diffusion in solid-state NMR, in W. S. Warren (ed). Advances in Magnetic and Optical Resonance, vol. 18, Academic Press, New York, 1994, pp. 1-116. 

Weigand, E., Demco, D.E., Blumich, B., and Spiess, H.W. (19%) Spatially resolved NMR spin diffusion in solid polymers. 

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