In rf-driven spin diffusion, a spin-lock ?eld of strength v1S is applied to the dilute S spins (13C,15N) during the mixing time.19 ,20 This spin-lock ?eld scales the chemical-shift differences among the S spins virtually to zero and decouples them from the abundant I spins (1H) both of these effects enhance the rate of spin diffusion among the, 10/27/1989 · Conclusions Rf-driven spin diffusion appears to be a promising tool for obtaining structurai information in solids us- ing natural abundance 3C samples. The application of a WALTZ- 17 sequence to 3C with simultaneous cw proton decoupling can yield an acceleration of 3C spin diffusion by a factor as high as 400 for rigid sol- ids compared to proton-driven spin diffusion in the laboratory.
Experimental build-up of the normalized rf-driven spin diffusion cross-peak intensity in 13 C natural-abundance adamantane as a function of P 2 (cos 1 ) 1 for 1 0°, 35.25°, and 90°.
A zero-angle sample spinning approach to obtain high-resolution solid-state spin – diffusion spectra is presented. During the mixing period of a two-dimensional spin – diffusion experiment, the rotation axis is aligned parallel to the external magnetic field and suitable multiple-pulse sequences are applied to enable efficient polarization transfer independent of the chemical-shift separation of the involved nuclei.
Increased spin diffusion sure of the dipolar coupling. An effective Hamiltonian for this in natural abundant 13C spins has also been observed at the experiment is derived, taking into account all chemical shift pa- rotational resonance criteria (19). rameters of the spins.
2/7/2008 · Experimental results obtained using CRDSD, rf-driven spin diffusion, and proton driven spin diffusion approaches on the NAVL single crystal are compared. Our experimental results suggest that the (15)N spin diffusion rate can be enhanced by about 1000 times using CRDSD than by the normal proton driven spin diffusion.
Spin diffusion , which can be defined as the transfer of spin polarisation induced by the dipolar interaction, is a ubiquitous transport mechanism in solids. Experimental observations of spin …
