Theoretical investigation of the structural, electronic, magnetic and elastic properties of binary cubic C15-Laves phases TbX2 (X = Co and Fe)
Theoretical investigation of the structural, electronic, magnetic and elastic properties of binary cubic C15-Laves phases TbX2 (X = Co and Fe)
复制标题
DOI：
10.1016/j.jallcom.2016.08.046
复制
发表时间：
2016-12-25
影响因子：
6.2
通讯作者：
Aissa, B.
中科院分区：
文献类型：
--
作者：
Bentouaf, A.;Mebsout, R.;Aissa, B.
我们报告的立方MgCu 2型二元Laves相TbCo 2和TbFe 2化合物的物理性质的全面的理论研究。采用密度泛函全势能线性缀加平面波（FP-LAPW）方法。我们采用广义梯度近似（GGA）来估计交换关联势和GGA+U（即Hubbard校正）计算来精确表征关联效应。平衡态的晶格常数a（0）、体积模量B和磁矩M与实验结果吻合较好。用GGA和GGA+U方法分别计算了TbCo_2和TbFe_2中Co和Fe的磁矩，发现Fe的磁矩值大于Co的磁矩值，GGA+U方法得到的磁矩值大于GGA方法得到的磁矩值。为了进一步了解与每个轨道相关的状态类型，分别使用GGA和GGA+U计算Co-3d和Fe-3d轨道的投影态密度。这项工作突出了相关电子处理的作用，这些二元Laves相化合物的准确描述。(C)2016由Elsevier B. V.出版
We report on a comprehensive theoretical investigation of the physical properties of the cubic MgCu2-type binary Laves phases TbCo2 and TbFe2 compounds. The density functional full-potential linearized augmented planewave (FP-LAPW) method was used. We adopted the generalized gradient approximation (GGA) to estimate the exchange correlation potential and the GGA+U (i.e. Hubbard correction) calculations in accurately characterizing the correlation effects. The lattice parameter a(0), bulk modulus B and magnetic moment M at the equilibrium state were found to well corroborate the experimental data. We have calculated the magnetic moments of Co and Fe in the TbCo2 and TbFe2, respectively, by using GGA and GGA+U methods, where the magnetic moments value of Fe was found to be higher than that of Co. The GGA+U gave higher value than that obtained by GGA. To obtain further insight into the type of states associated with each orbital, the projected density of states of the Co-3d and Fe-3d orbitals were calculated using GGA and GGA+U, respectively. This work highlights the role of the correlated electrons processing for an accurate description of these binary Laves phases compounds. (C) 2016 Published by Elsevier B.V.