Effect of the spin-orbit coupling and Hubbard corrections in predicting the electronic and magnetic properties of vacancy-ordered double perovskites A2WCl6 (A = Rb and Cs)

Abstract The structural, elastic, electronic, and magnetic properties of the vacancy ordered double perovskite compounds A 2 WCl 6 (A = Rb, Cs) have been investigated within the full-potential linearized augmented plane waves (FP-LAPW) method. The structural properties in the cubic phase were examined and are consistent with the available experimental results. The materials are more stable in the ferromagnetic phase. The mechanical, dynamical and the thermodynamical stability have also been verified. The electronic and magnetic properties were first calculated by GGA-WC approximation, the studied materials are found to be half-metallic. Including Hubbard correction (U), the W-d states move towards higher energy enlarging the band gap in the spin-down channel. The spin–orbit coupling (SOC) was added to GGA-WC+U which reveal that these compounds behave as semiconductors in both spin channels. The density of states showed that the valence band is mainly characterized by the W-d together with Cl-p states while the conduction band is dominated by W-d and (Cs/Rb)-d states. The calculated properties present semiconducting ferromagnetic nature that is considered as necessary factor in spintronics applications.