High-pressure neutron diffraction study of Pd3Fe

Abstract

High-pressure neutron diffraction data from powder and single-crystal samples of atomically disordered (Fm3m) and ordered (Pm3m) Pd 3 Fe were collected up to pressures of 15 GPa, and high-pressure SQUID magnetometry data were collected up to 6 GPa. The data show a subtle decrease in the magnetic moment with applied pressure, resulting in a transition to a paramagnetic state by approximately 8 GPa at 300 K. Diffraction results have been used to determine the equation of state, resulting in a bulk modulus of 176.78(9) GPa for the disordered powder and 187.96(7) GPa for the ordered single-crystal samples respectively, approximately 20% more compressible than previously reported from X-ray measurements. High-temperature SQUID magnetometry was used to confirm the ambient pressure Curie temperature of the sample (545 K), which was further investigated using high-temperature single-crystal neutron diffraction at ambient pressure.