A combined 17O RAPT and MQ-MAS NMR study of L-leucine.
نویسندگان
چکیده
We report the application of rotor-assisted population transfer (RAPT) to measure the quadrupolar coupling constant (C(q)) for spin 5/2 nuclei. Results from numerical simulations are presented on the magnitude of enhancement factor as a function of frequency offsets, i.e. the RAPT profile. Experimental O17 RAPT profile is traced for the amino acid L-leucine. In addition, results from MQ-MAS experiments are incorporated to determine the quadrupolar asymmetry parameter (eta(q)). Unlike previous reports, the O17 NMR parameters for an amino acid, L-leucine, is reported at a relatively low field of 9.4 T.
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ورودعنوان ژورنال:
- Solid state nuclear magnetic resonance
دوره 29 1-3 شماره
صفحات -
تاریخ انتشار 2006