2D CP/MAS 13C isotropic chemical shift correlation established by 1H spin diffusion.
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.
Max-Planck-Institut für Polymerforschung, Mainz, D-55021, Germany.
M
M
Wilhelm
H
H
Feng
U
U
Tracht
H W
HW
Spiess
D000409:Alanine / Q000032:analysis; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation*; D012680:Sensitivity and Specificity
D000409:Alanine