| 研究実績の概要 |
We continued the investigation of novel oxyhydride perovskite materials by studying 3d row as well as 4d and 5d elements at the B site. We synthesized for the first time a manganese oxyhydride compound with a Ruddlesden-Popper type layered perovskite derivative. This structure LaSrMnO3.3H0.7 was investigated by means of synchrotron x-ray diffraction and neutron powder diffraction. In this framework, we found that oxygen and hydrogen are disordered. The random distribution of O2- and H- leads to the random distribution of Mn2+ and Mn3+, giving a spin glass magnetic behavior for this system.
Investigation of the possible synthesis of 4d and 5d rows systems, AMO2H materials, proved to be difficult in comparison with 3d rows where SrCrO2H, BaScO2H and LaSrMnO3.3H0.7 were formed. From this we decided to focus our attention to creating a solid solution of (Ca,Sr,Ba)CrO2H and successfully formed a cubic phase up to Sr0.6Ba0.4CrO2H. Investigation of this solid solution indicated that substitution of strontium with calcium was difficult possibly in reason of the smaller size of Ca.
From this, we have understood this year the feasibility limits of the novel oxyhydride structure in relation with the tolerance factor and the size of the A site.
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