Abstract

The d 0 ferromagnetism of MgO containing neutral point defects has been investigated using the first-principles method. The generalized gradient approximation (GGA), local density approximation (LDA) and local density approximation with on-site effect U (LDA+ U) schemes were employed to describe the exchange correlation energy. Undoped MgO is found to be nonmagnetic. Neutral oxygen vacancies in the supercell induce no ferromagnetism, while neutral Mg vacancies could bring about large magnetic moments. The spin polarization of 2p electrons of oxygen atoms is responsible for the induced magnetic moments. The ferromagnetic moments enhance with an increase of the concentration of V Mg 0 vacancies. Ferromagnetism depends sensitively on the distribution of Mg vacancies. There may be a preferable occupation for V Mg 0 vacancies in the MgO lattice. The LDA+ U calculation indicates that a concentration of 6.25% V Mg 0 vacancies could convert the MgO insulator to half-metal. Our results may be valid for the region near the surface of nanograins.

Full Text
Paper version not known

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

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.