Quantifying the quadrupolar interaction by Sc-45-NMR spectroscopy of single crystals

Brauniger, Thomas und Zeman, Otto E. O. (2022): Quantifying the quadrupolar interaction by Sc-45-NMR spectroscopy of single crystals. In: Solid State Nuclear Magnetic Resonance, Bd. 117, 101775

Abstract

Single crystals of the compound [{Sc(H2O)5(mu -OH)}(2)]Cl-4 center dot 2H(2)O were studied by Sc-45-NMR, with the effect of the quadrupolar coupling interaction on the spectra of the spin-7/2 nucleus analysed in the hierarchical frame-work of perturbation theory. Orientation-dependent spectra acquired at B-0 =17.6 T showed strong second-order effects due to the comparatively large coupling constant of chi =§14.613 +/- 0.006§ MHz, with an associated asymmetry parameter of eta(Q) = 0.540 9 +/- 0.000 4. By analysing the splittings of the +/- 3/2 satellites, which in good approximation are subjected to first-order effects only, the full quadrupolar coupling tensor could be determined. The second-order effects caused by this tensor were calculated according to theoretical predictions for all orientations, and subtracted from both the centres of gravity of the satellites, and the central transitions. This allowed extraction of the full chemical shift tensor, with the eigenvalues being delta(11) = (5.6 +/- 0.9) ppm, delta(22) = (12.4 +/- 0.9) ppm, and delta(33) = (38.5 +/- 0.9) ppm. In spectra acquired at a lower magnetic field of B-0 = 9.4 T, third-order effects could be detected, and similarly quantified using analytical expressions.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Chemie und Pharmazie > Department Chemie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 0926-2040
• Sprache: Englisch