✦ LIBER ✦

Pulsed dynamic nuclear polarization at 5 T

✍ Scribed by S. Un; T. Prisner; R.T. Weber; M.J. Seaman; K.W. Fishbein; A.E. McDermott; D.J. Singel; R.G. Griffin

Publisher: Elsevier Science
Year: 1992
Tongue: English
Weight: 477 KB
Volume: 189
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(92)85152-z

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✦ Synopsis

A new dynamic nuclear polarization (DNP) technique utilizing high frequency, pulsed microwaves is described and demonstrated with observation of an Overhauser enhanced, "C magic angle spinning nuclear magnetic resonance spectrum of a powdered sample of the organic conductor, fluoranthenyl hexafluorophosphate ( (FA)*PF,). The spectrum was obtained at room temperature in a 5 T magnetic field, where the conduction electron spin resonance frequency is 140 GHz. A simple theory that accounts for the salient aspects of this pulsed DNP technique is presented. In systems where Overhauser mechanisms dominate the DNP, this new pulsed method can produce enhancements which are comparable to or greater than those obtained with conventional cw irradiation techniques, with lower average microwaves powers.

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