45Sc Solid State NMR studies of the silicides ScTSi (T=Co, Ni, Cu, Ru, Rh, Pd, Ir, Pt)

The silicides ScTSi (T=Fe, Co, Ni, Cu, Ru, Rh, Pd, Ir, Pt) were synthesized by arc-melting and characterized by X-ray powder diffraction. The structures of ScCoSi, ScRuSi, ScPdSi, and ScIrSi were refined from single crystal diffractometer data. These silicides crystallize with the TiNiSi type, space group Pnma. No systematic influences of the 45Sc isotropic magnetic shift and nuclear electric quadrupolar coupling parameters on various structural distortion parameters calculated from the crystal structure data can be detected. 45Sc MAS-NMR data suggest systematic trends in the local electronic structure probed by the scandium atoms: both the electric field gradients and the isotropic magnetic shifts relative to a 0.2 M aqueous Sc(NO3)3 solution decrease with increasing valence electron concentration and within each T group the isotropic magnetic shift decreases monotonically with increasing atomic number. The 45Sc nuclear electric quadrupolar coupling constants are generally well reproduced by quantum mechanical electric field gradient calculations using the WIEN2k code.

Graphical AbstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Arc-melting synthesis of silicides ScTSi. ► Single crystal X-ray data of ScCoSi, ScRuSi, ScPdSi, and ScIrSi. ► 45Sc solid state NMR of silicides ScTSi.