- I. Schnell, K. Saalwächter.
Length Determination in Natural Abundance by Inverse Detection in Fast-MAS
Solid-State NMR Spectroscopy.
J. Am. Chem. Soc.
124, 10938-10939 (2002).
(Supporting Information - pdf)
A solid-state 15N-1H correlation NMR experiment is presented, which
provides a substantial gain in signal sensitivity by 1H inverse detection under fast MAS conditions and allows
for the precise determination of NH bond lengths via heteronuclear 1H-15N dipole-dipole
couplings on samples naturally abundant in 15N. Pulsed-field gradients or, alternatively,
radio-frequency pulses ensure suppression of unwanted 1H signals. In this way, natural-abundance 15N-1H correlation NMR
spectroscopy becomes feasible in the solid state with experiment times of a
few hours. The dipole-dipole coupling constants are extracted from spinning
sideband patterns generated by recently developed recoupling strategies. The
information on 15N/1H chemical shifts and quantitative 15N-1H couplings can
readily be combined in a single two-dimensional spectrum using a