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Beerwerth, Joachim ; Siegel, Renée ; Hoffmann, Lars ; Plaga, Leonie S. ; Storek, Michael ; Bojer, Beate ; Senker, Jürgen ; Hiller, Wolf ; Boehmer, Roland:
From Ultraslow to Extremely Fast Dynamics in Sodium Nitrate : an ¹⁷O NMR Study.
In: Applied Magnetic Resonance.
Bd. 51
(2020)
Heft 7
.
- S. 597-620.
ISSN 1613-7507
DOI: https://doi.org/10.1007/s00723-020-01201-5
Abstract
Increasing dynamics in solids featuring nuclei subjected to second-order quadrupolar interactions lead to central-transition spectra that undergo two consecutive line-shaped transitions. Conventional motional narrowing occurs when the molecular exchange rate is on the order of the strength of the dominant interaction. In a second step, the resulting intermediately narrowed spectra change further when the motion becomes faster than the Larmor precession rate, leading to terminally narrowed spectra that can display a residual quadrupolar shift. We derive analytic expressions for this shift and analyze the quadrupolar central-transition spectra in terms of C-N symmetrical cone models. Increasing the number of sites to N >= 3, the terminally narrowed spectra remain unaltered, while the intermediately narrowed spectra remain unaltered only for N >= 5. This finding relates to the different (cubic vs. icosahedral) symmetries that are required to average out the spatial second- and fourth-rank terms in the second-order quadrupolar interaction. Following recent work (Hung et al., Solid State Nucl Magn Reson 84:14-19, 2017), O-17 NMR is applied to examine the three-site rotation of the nitrate group in NaNO3. Line shapes are measured and analyzed, and in addition to prior work, satellite-transition and stimulated-echo experiments are carried out. The final-state amplitudes extracted from the latter are reproduced using model calculations. It is shown how two-dimensional exchange spectra relating to N-site cone motions can be decomposed in terms of effective two-site-jump spectra. This latter approach is successfully tested for NaNO3.
Weitere Angaben
| Publikationsform: | Artikel in einer Zeitschrift |
|---|---|
| Begutachteter Beitrag: | Ja |
| Institutionen der Universität: | Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie > Lehrstuhl Anorganische Chemie III Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie > Lehrstuhl Anorganische Chemie III > Lehrstuhl Anorganische Chemie III - Univ.-Prof. Dr. Jürgen Senker Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie |
| Titel an der UBT entstanden: | Ja |
| Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik > 530 Physik 500 Naturwissenschaften und Mathematik > 540 Chemie |
| Eingestellt am: | 04 Aug 2020 10:27 |
| Letzte Änderung: | 07 Feb 2023 10:19 |
| URI: | https://eref.uni-bayreuth.de/id/eprint/56304 |