386.
Summary. A brief overview of our recent results concerning the application of 2D CRAMPS experiments to investigate a wide range of
materials is presented. The abilities of the 2D
1H–
1H spin-exchange technique to characterize the structure of organic solids as well as the limitations resulting from segmental
mobility and from undesired coherence transfer are discussed. Basic principles of
1H NMR line-narrowing and procedures for analysis of the spin-exchange process are introduced. We focused to the qualitative
and quantitative analysis of complex spin-exchange process leading to the determination of domain sizes and morphology in
heterogeneous multicomponent systems as well as the characterization of clustering of surface hydroxyl groups in polysiloxane
networks. Particular attention is devoted to the determination of the
1H–
1H interatomic distances in the presence of local molecular motion. Finally we discuss limitations of the
13C–
13C correlation mediated by
1H–
1H spin exchange to obtain structural constraints. The application of
Lee-Goldburg cross-polarization to suppress undesired coherence transfer is proposed.
Corresponding author. E-mail: brus@imc.cas.cz
Received May 28, 2002; accepted (revised) July 1, 2002
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