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2D CP/MAS 13C isotropic chemical shift correlation established by 1H spin diffusion.

M Wilhelm·H Feng·U Tracht·H W Spiess
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Abstract

A new 2D solid-state CP/MAS 13C NMR exchange experiment for through-space isotropic chemical shift correlation is proposed and demonstrated. Through-space correlation is established via a second cross polarization from 13C to 1H and subsequent 1H spin diffusion. A third cross polarization results in the final 13C-13C isotropic chemical shift correlation. The 1H spin diffusion time is a variable parameter allowing different mean square magnetization displacements to be probed. Experimental results on mixtures of differently 13C-labeled alanine and polyethylene indicate that this site-selective 2D technique can be used to characterize domain sizes and proximities over a wide range of length scales (1-200 nm) in solids such as polymers or biological materials.

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AlanineHumansMagnetic Resonance SpectroscopySensitivity and SpecificityJournal ArticleResearch Support, Non-U.S. Gov't

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M Wilhelm, H Feng, U Tracht, H W Spiess. 1998. 2D CP/MAS 13C isotropic chemical shift correlation established by 1H spin diffusion.. https://doi.org/10.1006/jmre.1998.1512

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