Broadband inversion for MAS NMR with single-sideband-selective adiabatic pulses.
We explain how and under which conditions it is possible to obtain an efficient inversion of an entire sideband family of several hundred kHz using low-power, sideband-selective adiabatic pulses, and we illustrate with some experimental results how this framework opens new avenues in solid-state NMR for manipulating spin systems with wide spinning-sideband (SSB) manifolds. This is achieved through the definition of the criteria of phase and amplitude modulation for designing an adiabatic inversion pulse for rotating solids. In turn, this is based on a framework for representing the Hamiltonian of the spin system in an NMR experiment under magic angle spinning (MAS). Following earlier ideas from Caravatti et al. [J. Magn. Reson. 55, 88 (1983)], the so-called "jolting frame" is used, which is the interaction frame of the anisotropic interaction giving rise to the SSB manifold. In the jolting frame, the shift modulation affecting the nuclear spin is removed, while the Hamiltonian corresponding to the RF field is frequency modulated and acquires a spinning-sideband pattern, specific for each crystallite orientation.
Centre de RMN à Très Hauts Champs, FRE 3008 CNRS/Ecole Normale Supérieure de Lyon/Université Claude Bernard Lyon 1, 69100 Villeurbanne, France.
Andrew J
AJ
Pell
Gwendal
G
Kervern
Lyndon
L
Emsley
Michaäl
M
Deschamps
Dominique
D
Massiot
Philip J
PJ
Grandinetti
Guido
G
Pintacuda
D009682:Magnetic Resonance Spectroscopy / Q000592:standards*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D016566:Organoselenium Compounds / Q000737:chemistry*; D012015:Reference Standards; D013725:Terbium / Q000737:chemistry*
D009942:Organometallic Compounds; D016566:Organoselenium Compounds; D013725:Terbium