Crystal structure and magnetic properties of LaCo13−xSix compounds

Abstract

Tetragonal LaCo_13−xSi_x compounds have been obtained by annealing cubic LaCo_13−xSi_x compounds. The space group for the tetragonal structure is I4/mcm. Atomic ordering occurs in the tetragonal LaCo_13−xSi_x compounds, i.e., Si atoms show a strong preference for occupying a specific crystallographic position. The tetragonal LaCo_13−xSi_x compounds are ferromagnetic with Curie temperatures higher than 900 K. The magnetic moment per Co atom in the tetragonal LaCo_13−xSi_x compounds decreases with Si content, which can be explained by the rigid‐band model. The tetragonal LaCo_13−xSi_x compounds are expected to be promising candidates for permanent magnets purpose.