Structural, electronic and magnetic properties of the double perovskite Pb2FeReO6

The structural, electronic and magnetic properties of the double perovskite Pb2FeReO6 have been studied by using the first-principles projector augmented wave (PAW) potential within the generalized gradient approximation (GGA) as well as taking into account the on-site Coulomb repulsive and exchange coupling interactions (GGA+U). The optimized crystal structure of the Pb2FeReO6 is a body-centered tetragonal (BCT) with a space group of I4/m and the lattice constants of a=b=5.59 Å and c=7.93 Å, consistent with the experimental results. The two axial transition metal and oxygen (TM–O) distances are slightly larger than the four equatorial TM–O distances and shows the existence of the Jahn–Teller structural distortion in FeO6 and ReO6 octahedra. The Fe3+ and Re5+ ions are in the states (3d5, S=5/2) and (5d2, S=1) with magnetic moments 3.929 and −0.831μB respectively and thus antiferromagnetic (AFM) coupling via oxygen between them. The half-metallic (HM) ferromagnetic (FM) nature implies a potential application of this new compound in magnetoelectronic and spintronics devices.