WSOLIDS1:
Static: Dipolar-chemical shift
(AB)

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This squeezed picture shows an example for the succesful simulation of a spectrum arising from the combined effect of chemical shift anisotropy and homonuclear dipolar coupling in a powder sample. It is the 31P NMR spectrum of pentacarbonyl molybdenum [bis(diphenylphosphino) methane], shown as absorption and first derivative spectrum, and the results have been published in:

K. Eichele, G. Ossenkamp, R. E. Wasylishen, T. S. Cameron, J. F. Britten:
Phosphorus-31 Solid-State NMR Studies of Homonuclear Spin Pairs in Molybdenum Phosphine Complexes: Single-Crystal, Dipolar-Chemical Shift, Rotational-Resonance and 2D Spin-Echo NMR Experiments
Inorg. Chem. 1999, 38, 639-651.

Click on the picture to have a better look.

screenshot of a simulation

Background

In addition to the chemical shift anisotropy (CSA), the spectrum of a spin pair will also depend on the direct dipolar coupling and potentially the indirect spin-spin coupling between both nuclei. Because both, the CSA and dipolar interaction, are tensorial interactions, the actual line shape also depends on their relative orientation. In contrast to the A2 and AX first-order spin systems, the line shape of a general homonuclear AB spin system may also depend on the relative orientations of the two chemical shift tensors.


[ Go Home ] | last modified: 16.08.2001