Suppression of radiation damping in high-resolution NMR.
The radiation damping field induced by an intense NMR line can be counterbalanced by a DANTE sequence of small flip angle pulses of opposite phase applied during the free induction decay. The transient NMR signal is acquired, one complex data point at a time, in the intervals between these DANTE pulses. As the intense signal decays, reducing the radiation damping field, the flip angles of the DANTE pulses are reduced at a matching rate. An experimental test on an aqueous solution of d-glucose demonstrates a reduction in linewidth at half height from 13.5 to 0.8 Hz, revealing a weak doublet response previously hidden under the broad water line.
Barjat
H
H
Department of Chemistry, Cambridge University, Lensfield Road, Cambridge, CB2 1EW, United Kingdom.
Mattiello
D L
DL
Freeman
R
R
D005947:Glucose / Q000737:chemistry / Q000528:radiation effects*; D007091:Image Processing, Computer-Assisted; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008280:Magnetics; D011840:Radiation, Nonionizing; D012680:Sensitivity and Specificity; D012996:Solutions / Q000737:chemistry / Q000528:radiation effects; D014867:Water / Q000737:chemistry*
D012996:Solutions; D014867:Water; D005947:Glucose