Magic-Angle and Dynamic-Angle Spinning NMR Study of the Si02 Polymorph Coesite
نویسندگان
چکیده
Five distinctly resolved I7O solid-state NMR resonances in room temperature coesite, an Si02 polymorph, have been observed and assigned using dynamic-angle spinning (DAS) at 11.7 T along with magic-angle spinning (MAS) spectra at 9.4 and 11.7 T. The I7O quadrupolar parameters for each of the five oxygen environments in coesite are correlated with the Si-0-Si bridging bond angles determined by diffraction experiments. The sign of e2qQ/h along with the orientation of the electric field gradient for oxygen in the Si-0-Si linkage were determined from a Townes-Dailey analysis of the data.
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