Rationalization of solid-state NMR multi-pulse decoupling strategies: Coupling of spin I = ½ and half-integer quadrupolar nuclei

• Published in: Journal of magnetic resonance (1997) Vol. 303; pp. 48 - 56
• Main Authors: Kouvatas, Cassandre, Kanwal, Nasima, Trebosc, Julien, Roiland, Claire, Delevoye, Laurent, Ashbrook, Sharon E., Le Fur, Eric, Le Pollès, Laurent
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-06-2019; Elsevier
• Subjects: Catalysis; Characterization of inorganic materials; Chemical Sciences; Cristallography; Half integer quadrupolar nucleus; Heteronuclear scalar interaction; Inorganic chemistry; Material chemistry; Multi-pulse decoupling; or physical chemistry; Resolution improvement; Simulations; Solid state NMR; Theoretical and; Simulations; Characterization of inorganic materials; Multi-pulse decoupling; Solid state NMR; Heteronuclear scalar interaction; Half integer quadrupolar nucleus; Resolution improvement; heteronuclear scalar interaction; half integer quadrupolar nucleus; characterization of inorganic materials; resolution improvement; Multi-Pulse decoupling; simulations
• ISSN: 1090-7807; 1096-0856
• DOI: 10.1016/j.jmr.2019.04.005

[Display omitted]
•Decoupling of heteronuclear scalar interaction between observed ½-spin nucleus and half-integer quadrupolar nuclei.•Case of Multi-Pulse (MP) decoupling scheme.•Influence of intrinsic material parameters and instrumental parameters on MP decoupling efficiency and enhancement of spectral resolution.•Rationalization of the MP parameterizing and instrumental set up.•Combination of numerical approach and experimental data.
In this paper we undertake a study of the decoupling efficiency of the Multiple-Pulse (MP) scheme, and a rationalization of its parameterization and of the choice of instrumental set up. This decoupling scheme is known to remove the broadening of spin-1/2 spectra I, produced by the heteronuclear scalar interaction with a half-integer quadrupolar nucleus S, without reintroducing heteronuclear dipolar interaction. The resulting resolution enhancement depends on the set-up of the length of the series of pulses and delays of the MP, and some intrinsic material and instrumental parameters. Firstly through a numerical approach, this study investigates the influence of the main intrinsic material parameters (heteronuclear dipolar and J coupling, quadrupolar interaction, spin nature) and instrumental parameters (spinning rate, pulse field strength) on efficiency and resolution enhancement of the scalar decoupling scheme. A guideline is then proposed to obtain quickly and easily the best resolution enhancement via the rationalization of the instrumental and parameter set up. It is then illustrated and tested through experimental data, probing the efficiency of MP-decoupling set up using this guideline. Various spin systems were tested (31P-51V in VOPO4, 31P-93Nb in NbOPO4, 119Sn-17O in Y2Sn2O7), combined with simulations results.