Systems with Further Anisotropic Internal NMR Interactions

SYSTEMS WITH FURTHER ANISOTROPIC INTERNAL NMR INTERACTIONS 

Many applications of solid state NMR techniques, exploiting the presence of homo- and/or heteronuclear spin interactions, have been reported for a large variety of chemicals (ranging from biochemically relevant molecular compounds, to organic polymers, crystalline inorganic solids and transition metal complexes). The topic has been reviewed recently [35]. Reports in the literature where Sn or Pb are involved in such studies are still very rare so that only a brief outlook is presented. Three topics will be mentioned Sn coupled to neighboured Sn coupled to neighboured F, and isolated 

It is a common situation in organotin chemistry that one or two chlorine atoms are directly bonded to tin. In solution state Sn NMR spectra the presence of the quadrupolar nuclei is usually reflected by just a moderate 

Similar effects can be expected for the situation where is bonded to Sn, and have already been reported [36]. 

The properties of isolated homonuclear spin pairs under MAS have recently become a focus of attention, both with a view to theory and application [39]. The careful study of spinning frequency and Bo-dependent effects in MAS spectra of homonuclear spin pairs is particularly rewarding since NMR information can be obtained which otherwise may only be obtained from single crystal NMR likewise, it is possible to determine geometric distances from MAS-dependent effects on powder samples. So far, the intriguing properties of homonuclear spin pairs have only been exploited for isolated pairs of abundant spin-1/2 nuclei—either by means of selective enrichment, or 

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