Submillimeter coils for stimulated-echo spectroscopy of a solid sodium ion conductor by nonselective excitation of MHz broad 23Na quadrupolar satellite spectra

• Published in: Solid state nuclear magnetic resonance 2017-04, Vol.82-83, p.16-21
• Main Authors: Jessat, T., Adjei-Acheamfour, M., Storek, M., Böhmer, R.
• Format: Article
• Language: English
• Subjects: Microcoils; Quadrupolar nuclei; Solid electrolytes; Solid-state NMR; Stimulated spin echoes
• ISSN: 0926-2040; 1527-3326
• DOI: 10.1016/j.ssnmr.2016.12.010

In solids the detection of ionic motion covering the time range of milliseconds and longer is often accomplished using stimulated-echo spectroscopy. For spectral line widths much below or much above 1MHz nonselective or fully selective radio-frequency pulse excitation, respectively, is typically applied in such experiments. To enable the study of samples with quadrupolarly broadened satellite spectra featuring intermediate widths (in the lower MHz range) the present work exploits microcoils. Using such coils, stimulated-echo spectroscopy can be performed under conditions of nonselective excitation for instance with 23Na as a nuclear probe. Nutation experiments carried out used to assess the coil performance. The impact of second-order quadrupolar interactions is studied using explicit density-matrix calculations. The applicability of the present approach is successfully tested for a sodium orthophosphate based solid ion conductor. [Display omitted] •Microcoils are useful for stimulated-echo studies of quadrupolar nuclei featuring MHz broad spectra.•Density matrix analysis reveals relative importance of first- and second-order quadrupolar effects.•Submillimeter coil performance is checked using nutation analysis.•Method is successfully applied to study motional correlation functions of a sodium-23ion conductor.