High-field QCPMG NMR of large quadrupolar patterns using resistive magnets.
Solid state nuclear magnetic resonance 2009 ; 36: 159-63.
Hung I, Shetty K, Ellis PD, Brey WW, Gan Z
DOI : 10.1016/j.ssnmr.2009.10.001
PubMed ID : 19913391
PMCID : 0
Abstract
Spectroscopy in a high magnetic field reduces second-order quadrupolar shift while increasing chemical shift. It changes the scale between quadrupolar and chemical shift of half-integer quadrupolar spins. The application of QCPMG multiple echo for acquiring large quadrupolar pattern under the high magnetic field of a 25 T resistive magnet is presented for acquiring large quadrupolar patterns. It shows that temporal field fluctuations and spatial homogeneity of the Keck magnet at the NHMFL contribute about +/- 20 ppm in line broadening. NMR patterns which have breadths of hundreds to thousands of kilohertz can be efficiently recorded using a combination of QCPMG and magnetic field stepping with negligible hindrance from the inhomogeneity and field fluctuations of powered magnets.