Abstract
First-principles calculations have been carried out to study the structural, electric, and magnetic properties of Ni3TeO6-type A2FeMoO6 compounds (A = Sc, Lu). Their electric and magnetic properties behave like room-temperature ferrielectric and ferrimagnetic insulators where polarization comes from the un-cancelled antiparallel dipoles of (A(1), Fe3+) and (A(2), Mo3+) ion groups, and magnetization from un-cancelled antiparallel moments of Fe3+ and Mo3+ ions. The net polarization increases with A’s ionic radius and is 7.1 and 8.7 μCcm−2 for Sc2FeMoO6 and Lu2FeMoO6, respectively. The net magnetic moment is 2 μB per formula unit. The magnetic transition temperature is estimated well above room-temperature due to the strong antiferromagnetic superexchange coupling among Fe3+ and Mo3+ spins. The estimated paraelectric to ferrielectric transition temperature is also well above room-temperature. Moreover, strong magnetoelectric coupling is also anticipated because the magnetic ions are involved both in polarization and magnetization. The fully relaxed Ni3TeO6-type A2FeMoO6 structures are free from soft-phonon modes and correspond to stable structures. As a result, Ni3TeO6-type A2FeMoO6 compounds are possible candidates for room-temperature multiferroics with large magnetization and polarization.
Highlights
Strong magnetoelectric coupling is anticipated because the magnetic ions are involved both in polarization and magnetization
To improve the net magnetization of ScFeO3, constructing ferrimagnetic structure by replacing one of the B-site Fe3+ by a dn (n < 5) ion is a possible way, which was done in the synthesized Bi2FeCrO6 (Cr3+: d3 compound28,29)
Strong magnetoelectric coupling is achieved since the electric polarization comes partly from the same magnetic ions
Summary
Strong magnetoelectric coupling is anticipated because the magnetic ions are involved both in polarization and magnetization. Ni3TeO6-type A2FeMoO6 compounds are possible candidates for room-temperature multiferroics with large magnetization and polarization. In order to meet these crucial requirements, searching for the multiferroics which have magnetic ions contributing simultaneously to electric polarization can be a good choice. All of them are found to be multiferroic materials and have the same polar structure as Ni3TeO63, ZnTiO320, and FeTiO321. The structural advantage is its ability to incorporate different magnetic transition-metal ions on all cation sites for realizing magnetoelectric coupling. Good examples are the Ni3TeO6 (Ni2NiTeO6) compound with nonhysteretic colossal magnetoelectricity[3], ScFeO3 (Fe takes both the B- and B′ -sites)[23,24] and Mn2FeMO6 (M = Nb, Ta, Mo, and W)[25,26,27] compounds with polar structure and antiferromagnetic or ferrimagnetic structure. To improve the net magnetization of ScFeO3, constructing ferrimagnetic structure by replacing one of the B-site Fe3+ by a dn (n < 5) ion is a possible way, which was done in the synthesized Bi2FeCrO6 (Cr3+: d3 compound[28,29])
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
