Structural and magnetic properties of [formula omitted] by neutron powder diffraction and electronic structure investigations

Abstract

Neutron powder diffraction, magnetic measurements and electronic band structure calculations were performed on PrCo3−xFex compounds. Our study confirms that samples crystallize in the PuNi3-type structure (space group: R3¯m, 166) for x≤1. The substitution of iron for cobalt atom leads to an increase of the unit cell volume. Neutron powder diffraction measurements at room temperature on PrCo2.5Fe0.5 demonstrate that iron atoms prefer to occupy the 18h crystallographic site of the PuNi3 structure (R3¯m). In addition to the experimental study, theoretical investigation of the electronic structure, stability as a function of x-rate, and magnetic property of the PrCo3−xFex compounds are studied by first-principle calculations. The density of states for the PrCo3−xFex compounds in the two directions of spin showed that the majority occupied states are dominated by the 3d states of M atoms (M=Co, Fe) with an electronic charge transfer from Pr to M. The magnetic anisotropy has been confirmed for PrCo3−xFex compounds, since non-collinear spin calculation with moment oriented along the c-axis has been found more stable than those along the (a,b) plane.