First-principles investigations of the magnetic properties of graphite boron nitride sheet induced by Fe doping

The first-principles spin polarization method is used to investigate the magnetic properties of graphite boron nitride (g-BN) sheet induced by Fe doping. We find that a nitrogen or boron atom substituted by Fe can induce a magnetic moment. From standard Mulliken population analysis, we also find that the magnetic moment is mainly dominated by Fe 3d states. Using Heisenberg exchange coupling theory, we study the exchange coupling mechanisms by constructing two-Fe centers in g-BN. The results show the presence of relatively strong exchange coupling for two-Fe substituted two-B atoms and the coupling is ferromagnetic. For the case of two-Fe substituted two-N atoms, the coupling is antiferromagnetic and the exchange coupling is very weak. The paper enriches recent molecular magnetic investigations.