Electrical resistivity and Mössbauer effect studies of Dy(Mn0.4−xAlxFe0.6)2 and Dy(Mn1−xFex)2 intermetallics

Electrical resistivity studies of Dy(Fe1−xCox)2 compounds

“…After the welding procedure there was no microscopically observable cracks. The four probe method mentioned previously, was used to measure electrical resistivities [9].…”

“…3) [17][18][19]. The procedure to determine ρ 0, ρ f (T) and ρ m (T) was somewhat improved as compared to the method described previously elsewhere [9]. Table 1 Crystal lattice parameter a, temperature θ, residual resistivity ρ 0 , magnetic hyperfine field µ 0 H hf [5,6], average number n of 3d electrons, squared splitting energy E 2 and Curie temperature T C of the Dy( [16,20] 140 [16] To describe the procedure it is useful to mention that for the low temperature region (T θ and T T C ), the expression (1) can be written as [17,19]:…”

“…The renewed parameters obtained from the last fitting, were used to calculate the phonon contribution ρ f (T) using the integral part in formula (4) [9,[17][18][19]. Subsequently subtracting from the experimental ρ(T) curve the corresponding fitted ρ 0 value and the corresponding calculated temperature dependence of ρ f (T), the magnetic contribution versus temperature i.e.…”

“…For the higher Co-substitutions the weak ferromagnetismtype behaviour of the M-sublattice appears. The filling-up of the minority 3d subband still proceeds and the observed field decreases gradually with n [5,6,9]. This Mn/Fe or Fe/Co replacement strongly influences the 3d-band and thus the magnetism and the hyperfine interactions of the compounds [5,6].…”

“…Additionally, the literature T C data for the Dy(Mn 1−x Fe x ) 2 and Dy(Mn 0.4−x Al x Fe 0.6 ) 2 series were taken into account [9,10]. These magnetic ordering temperatures are discussed qualitatively within the frame of the rigid band model.…”