NMR characterization of H2@C60 nitroxide derivatives and their nuclear spin relaxationw
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چکیده
H NMR of two H2@C60 nitroxide derivatives has been characterized indirectly by reducing to their corresponding hydroxylamines. Nuclear spin relaxation of the endohedral H2 and external protons of the H2@C60 nitroxide and its corresponding hydroxylamine were measured and analyzed. The observed spectra are consistent with negligible scalar coupling between the unpaired electron and the endo-H2. An unexpectedly large bimolecular relaxivity induced in the hydroxylamine by the corresponding nitroxide can be explained by rapid hydrogen atom transfer between the two species.
منابع مشابه
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تاریخ انتشار 2011