Thursday, May 25, 2006

CPL: Ashbrook and Wimperis: 2H DQMAS for monitoring chemical dynamics

Chemical Physics Letters
Volume 423, Issues 4-6 , 1 June 2006, Pages 276-281

2H double-quantum MAS NMR spectroscopy as a probe of dynamics on the microsecond timescale in solidsstar, open

Marica Cutajar, Sharon E. Ashbrook and Stephen Wimperis

a Department of Chemistry and WestCHEM, University of Glasgow, Glasgow G12 8QQ, United Kingdom
b School of Chemistry and EastCHEM, University of St Andrews, St Andrews KY16 9ST, United Kingdom


The sidebands observed in the magic angle spinning (MAS) NMR spectrum of a spin I = 1 2H nucleus may be very strongly broadened if motion is present in the solid. The broadening arises from interference between the line-narrowing effects of MAS and the dynamics-driven reorientation of the 2H quadrupole tensor. Here, we show that this motional broadening is absent or much reduced in the corresponding double-quantum MAS NMR spectrum. This observation suggests a new approach to studying dynamics in solids and examples are drawn from 2H MAS NMR of oxalic acid dihydrate, sodium tetrathionate dihydrate, and the synthetic polymer PMMA.

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