FIRST-PRINCIPLES STUDY ON THE ELECTRONIC STRUCTURES OF Gd PNICTIDES

In this article we present a first-principles calculation on the electronic structures and magnetism of Gd pnictides. Calculations are based on the local (spin-) density approximation of the density functional theory (DFT).The calculation method we used in this study is the linear muffin-tin orbitals in the atomic-sphere approximation (LMTO-ASA). Our result shows that in the non-spin polarized case the calculated band structures of Gd-V(V=N,P and As) exhibit characteristics of semimetals. After performing a wide band self-energy corrections, only the band structure of GdN is found to be a semiconductor with a narrow band gap (～019eV). Within the local-spin density approximations,the majority and minor spin bands of GdN display different features, i.e., the spin up band is semimetallic and the spin down band is semiconductor-like with a narrow gap (Eg≈036eV). All systems studied except GdN were found to be semimetallic with a hole section of the Fermi surface near Γ and an electron section near X.