%0 Journal Article %J Journal of Magnetic Resonance %D 1998 %T Surface selective H-1/Si-29 CP NMR by NOE enhancement from laser polarized xenon %A Pietrass, T. %A Seydoux, R. %A Pines, A. %K spins %X
The surface proton spin polarization created by the spin-polarization-induced nuclear Overhauser effect from optically polarized xenon can be transferred in a subsequent step by solid-state cross polarization to another nuclear spin species such as Si-29. The technique exploits the dipolar interactions of xenon nuclear spins with high gamma nuclei such as H-1, and is experimentally simpler than direct polarization transfer from Xe-129 to heteronuclei such as C-13 and Si-29. (C) 1998 Academic Press.
%B Journal of Magnetic Resonance %V 133 %P 299-303 %8 Aug %@ 1090-7807 %G English %UPorous silicon has been characterized by Si-29 nuclear magnetic resonance spectroscopy under conditions of static samples, magic angle spinning, decoupling and cross polarization. In a free induction decay experiment, two Si-29 resonances at -80 and -111 ppm were obtained. Cross polarization resulted in a single resonance at -97 ppm. Magic angle spinning and decoupling slightly reduce the linewidth of the Si-29 cross polarized signal, The minor narrowing effect and thr relaxation behavior in the laboratory and rotating frame indicate a homogeneous contribution to the linewidth. The relaxation data suggest that the resonance observed under cross polarization conditions arises from SiH or SiH2 structural elements.
%B Journal of Non-Crystalline Solids %V 202 %P 68-76 %8 Jul %@ 0022-3093 %G English %U