57Fe Mössbauer effect studies of Dy(Fe0.7−xAlxCo0.3)2 intermetallics

Abstract

It was previously found that the magnetic hyperfine fields observed at 57Fe nuclei (4.2 K) in the Dy(Mn1−xFex)2 and Dy(Fe1−xCox)2 intermetallics form a Slater–Pauling curve with a maximum hyperfine field for the Dy(Fe0.7Co0.3)2 compound. The Fe/Al substitution in the Dy(Fe0.7Co0.3)2 compound was studied in the present paper. The intermetallic series Dy(Fe0.7−xAlxCo0.3)2 was prepared and data of an X-ray analysis are presented (300 K). The cubic, MgCu2-type, Fd3m crystal structure was observed. 57Fe Mössbauer effect measurements for the series were performed (4.2, 77, 293 K) and the obtained hyperfine parameters are presented. The magnetic hyperfine fields form a separate branch of the Slater–Pauling curve. The data related to a possible band structure are qualitatively discussed within the frame of the Stoner model.