Abstract
We present the first successful in situ simultaneous measurement of the electrical resistance and X-ray diffraction of FeH x (x∼ 1) under high-pressure H2 up to 25.5 GPa and low temperatures down to 9 K. The electrical resistivity ρ showed a sharp increase with the formation of iron-hydride FeH x (x∼ 1) at 3.5 GPa. The ϵ′-phase of FeH x was found to be metallic up to 25.5 GPa. The ρ vs. T curves up to 16.5 GPa approximately follow Fermi-liquid law below 25 K. However, T 5 was found to be better fitting at 25.5 GPa. This change can be considered to be related to the previously reported ferromagnetism collapse at corresponding pressure.
Acknowledgements
This work is supported by the HYDROSTAR Project provided by the New Energy Development Organization (NEDO).