PHYS 576 |
| Solid state 67-Zn (spin 5/2) magic-angle spinning NMR spectra have been assigned for each of the 5 hydrates (0, 1, 4, 6, 7) of zinc sulfate. The spectra have moderate quadrupole couplings but otherwise their line shapes vary greatly. The identity of each sample was validated, usually by single crystal x-ray diffraction. Differential scanning calorimetry and thermogravimetric analysis (DSC and TGA) are highly self-consistent and were also used to characterize each hydrate and corroborate x-ray diffraction data. Differential scanning calorimetry data strongly indicate that powders of zinc sulfate hydrates retain their crystalline structure as they dehydrate due to heating. TGA data and DSC data together suggest that an uncharacterized hydrate (2 or 3) exists and is temporarily formed during the dehydration process. This work has yielded fundamental data that will advance the study of the relationship between zinc ssNMR parameters and coordination geometry. |
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General Experimental Physical Chemistry
7:30 PM-9:30 PM, Wednesday, August 19, 2009 Walter E. Washington Convention Center -- Hall D, Poster
Division of Physical Chemistry |