Electronic and thermoelectric properties of FeRh Pd-doped alloys: ab initio study

GIMAEV, RADEL R.; JULIA JIMÉNEZ, MARÍA; ZVEREV, VLADIMIR I.; KOMLEV, ALEKSEI S.; CABEZA, GABRIELA F.

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

ELSEVIER SCIENCE BV

Año: 2021

0304-8853

In this work, spin polarized total energy calculations were carried outto investigate the structural, energetic, magnetic and thermoelectricproperties of Fe50Rh50-xPdx (x = 1.9, 3.7,5.6, 6.3, 7.4, 9.3, 12.5, 18.8 and 25.0) and to compare with previous resultsof two-component undoped alloy. Some electronic characteristics were evaluatedcomputing the local density of orbital states (LDOS). The correspondingmagnetic moments per atom as well as thermal and electrical conductivity wereobtained to complete the analysis. We have found that in the range of Pdconcentrations studied, the cell parameter for the FM phase increases slightlyas x increases with increasing cell volume (0.2 to 1.9%). The structures are B2type. As x increases the AFM phase is more stable than the FM. Concerning theAFM phase, the tetragonal distortion along the z-axis is accompanied by aslight stabilization of the total energy with respect to the cubic phase. Thecell volume of the AFM phase is less than that corresponding to the FM phase(varying ~ 0.4 considering the cubic and ~ 0.9 considering the tetragonal). Thetransition temperature was estimated and the trend agrees with the experimentalevidence that the increase of Pd content shifts the transition temperature atlower temperatures. From the DOS (EF) we have also estimatedthe entropy change (DSe) obtaining valuesranging from 1 to 9 J/molK depending on the Pd content. Another consequence of the magnetic transition is the drop of theresistivity (ρ) in the FM phase compared to the AFM state in the studied rangefrom 100 K to 300 K. These results agree with literature experimental data.