摘要
利用基于密度泛函理论的第一性原理方法对未掺杂的锶铁氧体SrFe_(12)O_(19)、Co掺杂SrFe_(12)O_(19)及Co与Nd共掺杂SrFe_(12)O_(19)的晶体结构、电子性质及磁性性质进行了计算.结果表明:未掺杂的SrFe_(12)O_(19)晶体为半导体,体系中Fe原子表现为高自旋态,2a、2b、12k晶位Fe原子的磁矩与4f1、4f2晶位Fe原子的磁矩反平行排列,总磁矩为40μB;Co掺杂SrFe_(12)O_(19)后体系表现出金属性,Co与Fe原子均表现出高自旋态,Co原子磁矩为2.5μB,Fe原子磁矩为3.58μB,总磁矩为34μB;Co与Nd共掺杂SrFe_(12)O_(19)后Fe原子表现为高自旋态,磁矩为3.55μB,Nd原子被局域为高自旋态,磁矩为3μB,Co原子表现为低自旋态,体系总磁矩为62μB,掺杂后体系磁性明显增强.
The crystal structure, electronic and magnetic properties of pure strontium hexaferrite SrFe_12O_19, Co-doped and Co-Nd codoped SrFe_12O_19 were calculated by using the first principles approach based upon the density functional theory. The results show that pure SrFe12O19 is a semiconductor. All Fe ions have high spin states and the magnetic moment of Fe ions at the 2a, 2b and 12k sites are antiparallel to the rest of Fe atoms at 4f1 and 4f2 sites. The total magnetic moment of pure SrFe12O19 is 40μb. Co-doped SrFe_12O_19 shows metallic property and Fe, Co ions have high spin states, the magnetic moments of Fe, Co ions are 3.58 μ_B and 2.5 μ_B, respectively. The total magnetic moment of Co-doped SrFe_12O_19 is 34μB. Fe and Nd ions have high spin states and Co ions have low spin states in Co-Nd codoped SrFel2O19. The magnetic moments of Fe, Nd ions are 3.55 μB and 3 μ_B, respectively, and the total magnetic moment of Co-Nd codoped SrFe_12O_19 is 62μ_B. The magnetic moment of Co-Nd codoped SrFe_12O_19 is enhanced obviously.
出处
《宜宾学院学报》
2016年第6期86-90,共5页
Journal of Yibin University
基金
四川省教育厅科基金(13ZA0198)
宜宾市重点科技资助项目(2012SF034)
宜宾学院科研项目(2013QD10)
