Ab initio study of FeRh alloy properties

M. JULIA JIMÉNEZ; ANA B. SCHVVAL; GABRIELA F. CABEZA

COMPUTATIONAL MATERIALS SCIENCE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2020 vol. 172 p. 109385 - 109398

0927-0256

In this workthe structural, energetic, thermodynamic, magnetic and thermoelectric propertiesof FeRh alloy have been studied using first-principles calculations. Thestructural and magnetic results obtained for the FM phase are in agreement withexperimental and other theoretical calculated values (local magnetization ofabout 3 μBand 1 μB forFe and Rh atoms respectively). The transition AFM to the FM state is accompanied by a 2.4% increase in the volume of the cell and by 9.6 % in the Fe spin magneticmoment. The characterization of the AFM phase shows adistortion of the cubic and tetragonal cell to the orthorhombic solving theinstabilities observed in the phonon band structures curves of thecorresponding to cubic structure. Thestability of the AFM configurations was corroborated with molecular dynamics(MD) simulations. The magnitude of the Seebeck coefficient increases with thetemperature at a certain chemical potential. While the magnitude of theelectrical conductivity does not present meaningful changes with thetemperature in the selected values, the thermal conductivity increases with thetemperature. Another consequence of the AFM to FM transition is the drop of theresistivity ρ in the FM phase as compared to the AFM state. Basedon the results obtained using MDsimulations from stable AFM configurations and the results ofentropy changes, the configuration AFM-B (type I) could be identified as themost favorable in achieving the metamagnetic phase transition.