Chemical shift anisotropy amplification.
A new NMR experiment which allows a measurement of the chemical shift anisotropy (CSA) tensor under magic angle spinning (MAS) is described. This correlates a fast MAS spectrum in the omega2 dimension with a sideband pattern in omega1 in which the intensities mimic those for a sample spinning at a fraction of the rate omega r/N, and these sidebands result from an amplification by a factor N of the modulation caused by the CSA. Standard methods can be used to extract the principal tensor components from the omega1 sideband patterns, and the nature of the experiment is such that the use of a large number of t1 increments can be avoided without compromising the resolution of different chemical sites. The new experiment is useful for accurately measuring narrow shift anisotropies.
Shao
Limin
L
School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
Crockford
Charles
C
Geen
Helen
H
Grasso
Giuseppe
G
Titman
Jeremy J
JJ
D000465:Algorithms; D016880:Anisotropy; D002247:Carbon Isotopes; D003198:Computer Simulation; D005998:Glycine / Q000032:analysis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008757:Methylglucosides / Q000032:analysis / Q000737:chemistry*; D008956:Models, Chemical; D011786:Quality Control; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D013113:Spin Labels
D002247:Carbon Isotopes; D008757:Methylglucosides; D013113:Spin Labels; C027020:methylglucoside; D005998:Glycine