CoRuXAl (X = Mo, Tc, Re) Quaternary Heusler Alloys: Electronic and Magnetic Properties Examined with Density Functional Theory (DFT) and Effective Field Theory (EFT)

CoRuXAl(X=Mo, Tc, Re) quaternary heusler alloys electronic and magnetic properties<br>examinate with Density Functional Theory (DFT) and Effective Field Theory (EFT).<br>Structures have a 216 space group family like LiMgPdSn and f-43m symmetry. Wyckoff<br>positions in the unit cell are based on studies in the literature utilized with the form<br>(0,0,0)/(0.25,0.25,0.25)/(0.5,0.5,0.5)/(0.75,0.75,0.75). According to unit cell structures<br>optimization lattice parameters of CoRuXAl(X=Mo, Tc, Re) alloys obtained 6.0350 Å,<br>5.9637 Å, 5.9868 Å respectively. EFT DFT and total magnetization calculations were<br>made according to the optimization data of the alloys. CoRuXAl(X=Mo, Tc, Re) alloys<br>and total magnetization obtained 1.9807 , 1.0552 and 1.0121<br>respectively. Most contribution of this total magnetizations CoRuXAl(X=Mo, Tc, Re)<br>alloys originated of Co atoms with value of 1.451 (%73), 1.098 (%96) and<br>1.041 (%97) respectively. Birch–Murnaghan equation of state is used frequently<br>while getting volume equilibirium, and that parameter is obtained for CoRuXAl(X=Mo,<br>Tc, Re) alloys 219.8107 (a.u.3), 212.1100 (a.u.3) and 214.5858 (a.u.3) respectively. As a<br>result of Ferromagnetic and Nonmagnetic calculations, the curie temperatures of<br>CoRuXAl(X=Mo, Tc, Re) alloys were found 1840, 953, 853 K<br>respectively. Bandstructure energy gaps and density of states have been calculated<br>optimized volume-energy parameters. When the band structures are examined, the state<br>lines for one spin state are found in both the valence and conduction bands and show<br>metallic character, while a gap is observed at the Fermi level in the other band state. The<br>bandgaps of CoRuXAl(X=Mo, Tc, Re) alloys 0,1249 eV, 0,30811 eV and 0,2236 eV<br>respectively. Hysteresis graphics obtained with EFT calculations. These alloys can be<br>good candidade for spintronic applications. The results obtained are in agreement with<br>the literatüre values.