A 45Sc-NMR and DFT calculation study of crystalline scandium compounds

Abstract

A series of scandium compounds, namely ScPO4, ScOF, Li3Sc(BO3)2, and CaSc2O4, were prepared according to procedures described in the literature, and then characterised by powder X-ray diffraction and solid-state 45Sc-NMR spectroscopy. By computer fitting, the quadrupolar interaction parameters χ and η, as well as the isotropic chemical shifts δiso were extracted from the NMR spectra. For comparison and site assignment of 45Sc, density functional theory (DFT) calculations of the EFG tensor were carried out with the Castep code. For the compounds with a well-defined formal coordination number (CN), a convincing linear correlation between CN and isotropic chemical shift could be established.