Mossbauer spectra of MnFez04 with various particle sizes in a longitudinal 50 kOe magnetic field show that the Fe ion occupancy of the A and B crystallographic sites depends on the particle size. The elevated N6el temperatures with decreasing particle sizes are attributed to an increased iron occupancy on the A sites; this in turn leads to an increase in the total superexchange interaction.

The high spin complex Fe(I1) (N, N'-dicyclohexylthiourea)~(C10~)~ exists in two forms which only differ in the distortion from octahedral symmetry of the environment of the Fe ion. Thermodynamic data for the transformation from one form to the other as obtained from Mossbauer spectroscopy are presented and a method to derive kinetic parameters is described.

The structural transformation of substituted hexagonal ferrite powders BaFetoCoTiO~s prepared by mechanical milling, was investigated as a fimction of grinding time by means of MOssbauer spectrometry and static magnetic measurements. A spin reorientation is clearly evidenced from the temperature dependence of the hyperfine parameters and of the initial magnetic permeability on the powder mechan...

We have seen, by Mossbauer spectroscopy, magnetization and resistivity, changes on the physical properties of the aFe20Ni6oB20 alloy induced by thermal relaxation, notedly increases in T, and resistivity. These changes can be explained by modifications of the chemical short range order around Fe favouring the formation of Fe-Ni pairs.

Recent studies on TRIP-assisted multiphase steels have emphasised the drastic importance of the bainitic transformation in the optimisation of properties. Bainitic ageing is necessary for the stabilisation of austenite with respect to the martensitic transformation. This metastable retained austenite can still transform to martensite when plastically deformed (TRIP effect). The present work dea...

The effect of pressure on the M6ssbauer resonance in hemin and in iron phthalocyanine has been measured. In these initial studies unenriched compounds were used. The hemin was material supplied by Dr. Lowell Hager of the Division of Biochemistry. The iron phthalocyanine was obtained from E. I. DuPont de Nemours Company and was resublimed in our laboratory. The high-pressure M6ssbauer techniques...

Abstract M-type Barium hexaferrite is a famous hard magnetic material with hexagonal crystal structure. La substituted hexaferrite, Ba (1-x) (x) Fe 12 O 19 , (where, x = 0.25 and 0.30) were synthesized using ball milling followed by sintering at 1300 °C for 5 hours. X-ray diffraction patterns reveal the formation of single-phase magnetoplumbite structure barium which belongs to P6 3 /mmc space ...