Abstract
The magnetic field effect on the structural property of a ferromagnetic compound MnFeP0.5As0.5 was investigated by powder X-ray diffraction measurement in magnetic fields up to 5 T. The compound with the hexagonal Fe2P-type structure shows a field-induced isostructural transformation with a hysteresis by applying magnetic field, accompanied by the metamagnetic transition from the paramagnetic to ferromagnetic state just above the Curie temperature of 284 K. In this transformation, the a parameter expands by 0.5% whereas the c parameter contracts by 1%. However, the cell volume slightly and continuously decreases with increasing magnetic field through the transformation.
