Direct synthesis of chromium perovskite oxyhydride with a high magnetic-transition temperature

Year: 2014 DOI: 10.1002/anie.201405453

Extra Information

Cédric Tassel, Yoshihiro Goto, Yoshinori Kuno, James Hester, Mark Green, Yoji Kobayashi, Hiroshi Kageyama.   Angewandte Chemie International Ed., 2014, 53, 10377-10380.

Abstract

We report a novel oxyhydride SrCrO2H directly synthesized by a high-pressure high-temperature method. Powder neutron and synchrotron X-ray diffraction revealed that this compound adopts the ideal cubic perovskite structure equation imagewith O2−/H disorder. Surprisingly, despite the non-bonding nature between Cr 3d t2g orbitals and the H 1s orbital, it exhibits G-type spin ordering at TN≈380 K, which is higher than that of RCrO3 (R=rare earth) and any chromium oxides. The enhanced TN in SrCrO2H with four Cr-O-Cr bonds in comparison with RCr3+O3 with six Cr-O-Cr bonds is reasonably explained by the tolerance factor. The present result offers an effective strategy to tune octahedral tilting in perovskites and to improve physical and chemical properties through mixed anion chemistry.