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arXiv · 1902.08540

On the preparation and NMR spectroscopic characterization of potassium aluminium tetrahydride KAlH4

Bodo Zibrowius·Michael Felderhoff
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Abstract

Potassium aluminium tetrahydride KAlH4 of high phase purity (space group Pnma (62)) was synthesized via a mechanochemical route. The thus obtained material was studied by 27Al and 39K MAS NMR spectroscopy. For both nuclei precise data for the isotropic chemical shift and the quadrupole coupling at T=295 K were derived (27Al: delta_iso=(107.6+-0.2) ppm, C_Q = (1.29+-0.02) MHz and eta = 0.64+-0.02; 39K: delta_iso=(6.1+-0.2) ppm, C_Q = (0.562+-0.005) MHz and eta = 0.74+-0.02). The straightforward NMR spectroscopic approach applied here should also work for other complex aluminium hydrides and for many other materials containing half-integer nuclei experiencing small to medium-sized quadrupole couplings.

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Bodo Zibrowius, Michael Felderhoff. 2019-02-22. On the preparation and NMR spectroscopic characterization of potassium aluminium tetrahydride KAlH4. https://doi.org/10.1039/c9cp01059a

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