The relationship between atomic structure and magnetic property of amorphous Fe₇₈Si₉B₁₃ alloy at different pressures

The structural and magnetic property of amorphous Fe₇₈Si₉B₁₃ alloy at different pressures up to 282.1 GPa were investigated by ab initio molecular dynamics simulations. With the pressure increasing, the structural evolution of amorphous Fe₇₈Si₉B₁₃ alloy can be approximately divided into three regions, and the reduction of the interatomic distance leads to the exponential decrease of the average magnetic moment per Fe atom. Further, to establish the relationship between structure and atomic magnetic moment at a constant pressure, we focus on two types of polyhedra centered by Fe atoms in amorphous Fe₇₈Si₉B₁₃ alloy at 0.0 GPa. The result shows that the magnetic moment of central Fe atom is also influenced by the chemical composition besides the interatomic distance. For central Fe atom, more surrounding Fe atoms correspond to a larger magnetic moment, while the surrounding Si atoms is not conducive to the magnetic moment.