C、N、O 掺杂 CuBr 和 CuCl 的电子结构和磁性的第一性原理研究

摘要

The possibilities of half -metallic ferromagnetism in cuprum halides ( CuCl and CuBr ) with nonmag-netic sp elements C, N and O as dopants have been explored using the first principles plane wave pseudo poten -tial method based on density functional theory ( DFT) in combination with the generalized gradient approximation ( GGA).We investigate the electronic structure and magnetic properties in cuprum halides doped with non -mag-netic elements by calculating the total energy system , energy band , the density of states and partial density of states.There gives the analysis of the change of magnetic moments as a function of pressure.Our calculations re-veal that O-and N-dopants can induce a stable ferromagnetic state in CuCl , and that its ferromagnetism decreases and finally a magnetic phase transition from ferromagnetic ( FM) to nonmagnetic ( NM) phase occurs with the in-creasing pressure.%本文基于密度泛函理论（ DFT）结合广义梯度近似（ GGA），采用第一性原理的平面波赝势方法，探究非磁性sp元素（C、N和O）掺杂卤化物（CuCl和CuBr）是否能诱导产生半金属铁磁性.通过计算体系总能量、能带、态密度和分态密度，分析了非磁性元素掺杂卤化物体系的电子结构和磁性；通过对材料加压，给出了体系铁磁性随压强变化的趋势并作了分析.最后计算显示， O和N掺杂能诱导CuCl 产生稳定的半金属铁磁性，随着压强的增大CuCl0.75 N0.25和CuCl0.75 O0.25的铁磁性减弱最终发生磁相变由铁磁态（FM）转变为非铁磁态（NM）.