Inorganic Chemistry, Vol.56, No.9, 4840-4845, 2017
Pressure-Stabilized Cubic Perovskite Oxyhydride BaScO2H
We report a scandium oxyhydride BaScO2H prepared by solid state reaction under high pressure. Rietveld refinements against powder synchrotron X-ray and neutron diffraction data revealed that BaScO2H adopts the ideal cubic perovskite structure (Pm (3) over barm), where oxide (O2-) and hydride (H-) anions are disordered. H-1 nuclear magnetic resonance (NMR) spectroscopy provides a positive chemical shift of about +4.4 ppm, which can be understood by the distance to the nearest (and possibly the next nearest) cation from the H nucleus. A further analysis of the NMR data and calculations based on ab initio random structure searches suggest a partial cis preference in ScO4H2 octahedra. The present oxyhydride, if compositionally or structurally tuned, may become a candidate for H- conductors.