First-principles calculations to investigate electronic, magnetism, elastic properties of Tb_xDy_1-xFe₂ (x = 0, 0.25, 0.5, 1)

Electronic, magnetism, elastic properties are studies about Tb_xDy_1-xFe₂ (x = 0, 0.25, 0.5, 1), (i.e. four compounds: DyFe₂, Tb_0.25Dy_0.75Fe₂, Tb_0.5Dy_0.5Fe₂, TbFe₂), which is used the first principle based on density functional theory (DFT). The results have shown that these four compounds have obvious metallicity regarding the calculation of electronics properties. About magnetism, Tb_0.25Dy_0.75Fe₂ is better than other compounds, because its magnetic moment is the largest. Besides, analysis of elastic constants shows that all four compounds have mechanical stability. Further, Tb_0.25Dy_0.75Fe₂ has better ductility than the other three compounds. Based on the excellent magnetism and mechanical properties of Tb_0.25Dy_0.75Fe₂, it is providing candidate materials for the magneto-strictive materials using in the field of magnetic field sensing. Lastly, the concentration of widely used Terfenol-D (Tb_0.3Dy_0.7Fe₂) is near the concentration range of Tb_0.25Dy_0.75Fe₂, so it may be similar properties to Tb_0.25Dy_0.75Fe₂. Therefore, this work is also provided a prediction for the microscopic properties of Terfenol-D (Tb_0.3Dy_0.7Fe₂) materials. And then, it is provided a reference for rare earth magneto-strictive materials, which is currently less studied based on first-principles calculations.