Ni_4PrB的电子结构和磁性能研究  

Study of Ni_4PrB electronic structure and magnetism

作　　者：易勇[1,2] 李恺[1] 丁志杰[1,2] 易早[1] 罗江山[1] 唐永建[1] 

机构地区：[1]中国工程物理研究院激光聚变研究中心,绵阳621900 [2]四川省非金属复合与功能材料重点实验室-省部共建国家重点实验室培育基地,绵阳621010

出　　处：《物理学报》2011年第10期629-634,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10476024)资助的课题~~

摘　　要：考虑Pr-4f及Ni-3d电子间的库仑作用U和交换作用J,采用局域自旋密度近似LSDA(Local spin-density approximation)及LSDA+U(在位库仑势)近似,对Ni4PrB化合物进行结构优化,并计算体系电子结构,能带结构和磁性能.结果显示,Ni4PrB具备金属半导体性质,存在Pr-Ni铁磁耦合.U的引入对体系磁特性和结构稳定性有关键作用,加U前体系磁性来源为Ni原子磁矩,加U后体系磁性来源为Pr原子,且体系稳定性提高,U值的作用对于修正体系强关联有重要影响,可以合理描述由强关联和自旋排斥引发的排斥效应.Considering the Coulomb potential and the exchange action,electronic structure,band structure and magnetic properties of the compound Ni4PrB within the local spin-density approximation（LSDA） and the LSDA＋U approximation are studied through numerical simulation.The simulation results show that this system is a metallic semi-conductor and has Pr-Ni ferromagnetic coupling.The added Coulomb U effect can strongly affect magnetic properties and stable structure,and the total magnetic moment is provided by the local Ni magnetic moment before adding U effect,when the U effect is added to the system,the total magnetic moment is provided by the local Pr magnetic moment,and the system has a high structure stability.So U effect affects strongly the strong correlation,then it can describe reasonably the strong correlation and the exclusion effect caused by the spin exclusion.

关 键 词：密度泛函理论 电子键结构 磁性能 稀土过渡金属间化合物 

分 类 号：O482.5[理学—固体物理]