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 lo cal (spin-) density approximation of the density functional theory (DFT). T he calculation method we used in this study is the linear muffin-tin orbita ls in the atomic-sphere approximation (LMTO-ASA). Our re suit 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 ban d self-energy corrections, only the band structure of GdN is found to be a semiconductor with a narrow band gap (similar to 0.19 eV). Within the local -spin density approximations, the majority and minor spin bands of GdN disp lay different features, i.e., the spin up band is semimetallic and the spin down band is semiconductor-like with a narrow gap (E-g approximate to 0.36 eV). All systems studied except GdN were found to be semimetallic with a h ole section of the Fermi surface near Gamma and an electron section near X.