摘要
First-principle calculation was used to investigate the magnetic properties, electronic structure and bonding mechanism of FeF2. By calculating the lattice parameters and magnetic moment as a function of effective interaction parameter （Ueff）, it is found that the optimum value of Uefr is equal to 4 eV, the magnetic moment is 3.752 μB and the value of c/a is 0.704, which are in good agreement with the experiment results. Simultaneously, on the basis of GGA＋U method, the electronic structure and bonding mechanism of FeF2 were investigated by the analysis of electron localization function, Bader charge and total charge density. The results show that the bonding behavior between Fe and F atoms is a combination of ionic and covalent bond.
采用第一性原理方法研究FeF2的磁性、电子结构和成键机理。通过计算不同U值下的的晶格参数和磁矩,获得最佳的有效U值(Ueff)为4eV,此时计算Fe的磁矩和晶格参数c与a的比值分别3.752μB和0.704,与实验结果吻合。此外,基于GGA+U方法,利用对电子局域函数,Bader电荷和总电荷的分析来研究FeF2的电子结构和成键机理,结果表明Fe和F之间含有离子键和共价键的特征。
基金
Foundation item: Project (20871101) supported by the National Natural Science Foundation of China
Project (09C945) supported by the Scientific Research Fund of Hunan Provincial Education Department,China
