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The results of magnetic properties of ThFexAl12–x powder samples with iron concentration x = 4, 4.5 and 5, studied by means of X-ray (XD) and neutron diffraction (ND) techniques as well as the Mössbauer spectroscopy with the monochromatic circularly polarised source (MCPMS), and magnetisation measurements using vibrating sample magnetometer (VSM) are presented. Unpolarized neutron diffraction pattern leaves no doubts that the modulated magnetic structure is observed in the tetragonal ThFe4Al8 compound. The interpretation of our neutron data requires the presence of non-zero magnetic propagation vectors different from the nuclear one. ThFe4Al8 sample has double spiral structure with moments rotating in a plane perpendicular to the wave vector as well as to . Both of them are temperature independent in the range 1.5 K–70 K. The value of iron magnetic moment is close to 1 μB/Fe atom at 1.5 K.

Abstract: The results of the Mssbauer effect measurements on bcc Cr rich Cr-Fe-Mn alloys in temperature range 12–296 K in zero- and in applied magnetic fields are reported. Monochromatic, circularly polarized radiation was used for investigation of iron moments alignment. Strong enhancement of internal hyperfine magnetic field induced by the applied magnetic field was detected and explained as due to dynamical effects. At high temperatures alignment of iron moments in antiferromagnetic phase is weakly magnetic field-dependent. At low temperatures the average hyperfine magnetic field is antiparallel to the net magnetization showing that iron moments are partly ordered by the applied field.

Abstract: Properties of amorphous alloy Fe0.66Er0.19B0.15 are reported. A reorientation of the Fe and Er magnetic moments during sample cooling through the compensation point in a large magnetic field is found by means of monochromatic circularly polarised radiation.

Abstract: Monochromatic, circularly polarized radiation brings useful information on orientations of hyperfine fields in investigation of magnetic materials. This information can be extracted even from poorly resolved spectra by a model free method. In particular, the z-component of the average hyperfine magnetic field is given simply by a “center of gravity” of the difference between the spectra measured with two opposite polarizations. The efficiency of such an approach is demonstrated on the example of the 57Fe h.m.f. in bcc Cr–Fe–Mn alloys.