- K. Schmidt-Rohr, K. Saalwächter, Shu-Feng Liu, Mei Hong.
in Rigid Solids by 1H Detection.
J. Am. Chem. Soc. 123, 7168-7169 (2001).
A novel technique for detecting 2H NMR spectra
in partially deuterated solids with high sensitivity, proton
inverse-detected deuteron (PRIDE) NMR, is introduced. The
deuteron spectrum of a non-spinning solid is recorded indirectly through its
modulation of the 108-times stronger 1H signal
in a 1H-2H
heteronuclear multiple-quantum coherence experiment. In solids, this requires
homonuclear proton decoupling, using MREV-8 during excitation and reconversion
of the heteronuclear coherence, and a magic-sandwich echo before 2H evolution.
Detection of the 1H signal under pulsed spin-lock increases the sensitivity
further. The PRIDE technique is demonstrated on a 13% deuterated amorphous
polymer with the full 120-kHz quadrupolar splitting. A useful Pake pattern is
obtained on only 2 mg of the material in a 5-mm coil, within 40 minutes; the
sensitivity is approximately 15-fold enhanced. Suppression of D2O signal by the technique is also demonstrated.