First-principle Studies Of Low Dimensional Materials

The dissertation is devoted to the first principle study of magnetic properties of the low dimensional materials. The concerned systems include 2-D AlN and BN graphitic nanobelts and the CO3O4 nanoparticles and we study the properties of geometry, electronic structure and magnetic order.Firstly, we briefly introduce the basic concept of DFT and review its recent progress. Meanwhile we discuss the basic idea of first principle method based on density functional theory (DFT) and its numerical methods. Then we introduce the application realm of DFT and some calculation code package.Second, we describe the nature of IIIA-nitride and the properties as well as research background of AIN and BN. Then we build up the first principle calculation method and model on graphitic AlN and BN nanobelts, analyzing and discussing the calculated stable structures, electrical and magnetic properties. When it comes to the CO3O4 nanoparticles, we introduce the properties of CO3O4 and study the possible origin of ferromagnetism:vacancy-induced ferromagnetism.