%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 %U ://WOS:000075748200008 %N 2 %M WOS:000075748200008 %! Surface selective H-1/Si-29 CP NMR by NOE enhancement from laser polarized xenon %R Doi 10.1006/Jmre.1998.1447 %0 Journal Article %J Journal of Non-Crystalline Solids %D 1996 %T Si-29 high resolution solid state nuclear magnetic resonance spectroscopy of porous silicon %A Pietrass, T. %A Bifone, A. %A Roth, R. D. %A Koch, V. P. %A Alivisatos, A. P. %A Pines, A. %K dipolar %X

Porous 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 ://WOS:A1996VE40600008 %N 1-2 %M WOS:A1996VE40600008 %! Si-29 high resolution solid state nuclear magnetic resonance spectroscopy of porous silicon %R Doi 10.1016/0022-3093(96)00144-5 %0 Journal Article %J Journal of Magnetic Resonance Series A %D 1995 %T Spin-Polarized Xe-129 Gas Imaging of Materials %A Song, Y. Q. %A Gaede, H. C. %A Pietrass, T. %A Barrall, G. A. %A Chingas, G. C. %A Ayers, M. R. %A Pines, A. %K xenon %B Journal of Magnetic Resonance Series A %V 115 %P 127-130 %8 Jul %@ 1064-1858 %G English %U ://WOS:A1995RL47400017 %N 1 %M WOS:A1995RL47400017 %! Spin-Polarized Xe-129 Gas Imaging of Materials %R Doi 10.1006/Jmra.1995.1157 %0 Journal Article %J Physical Review Letters %D 1995 %T Surface Study of Supported Metal Particles by Xe-129 Nmr %A Bifone, A. %A Pietrass, T. %A Kritzenberger, J. %A Pines, A. %A Chmelka, B. F. %K states %B Physical Review Letters %V 74 %P 3277-3280 %8 Apr 17 %@ 0031-9007 %G English %U ://WOS:A1995QT44900047 %N 16 %M WOS:A1995QT44900047 %! Surface Study of Supported Metal Particles by Xe-129 Nmr %R Doi 10.1103/Physrevlett.74.3277