DyNi2Mn—magnetisation and Mössbauer spectroscopy

Abstract

The physical properties of DyNi 2 Mn doped with 57 Fe have been investigated by X-ray diffraction, magnetisation (10-300 K) and 57 Fe Mössbauer spectroscopy measurements (5-300 K). DyNi 2 Mn( 57 Fe) crystallizes in the MgCu 2 -type cubic structure (Fd − 3m space group). The ordering temperature is found to be T C = 99(2) K, much higher than those of DyNi 2 (∼22 K) and DyMn 2 (∼35 K). Analyses of isothermal M-H curves and the related Arrott plots confirm that the magnetic phase transition at T C is second order. The magnetic entropy change around T C is 4.0 J/kg K for a magnetic field change of 0 T to 5 T. The spectra above T C exhibit features consistent with quadrupolar effects while below T C the spectra exhibit magnetic hyperfine splitting. The Debye temperature for DyNi 2 Mn has been determined as θ D = 200(20) K from a fit to the variable temperature isomer shift IS(T).

Concluding remarks to ICAME2011

“…My attendance at ICAME2011 was supported by Discovery Project DP110102386 from the Australian Research Council [4].…”