Moessbauer spectra of titanomagnetite: A reappraisal.

Structure, Cation Distribution, and Properties of Nanocrystalline Titanomagnetites Obtained by Mechanosynthesis: Comparison with Soft Chemistry

“…Clear differences exist, however, from the spectrum published by Melzer et al for a titanoferrite of the same composition (58). In particular, the hyperfine field of the outer sextet is much larger in our case, H1"486 kG, than for the titanomagnetite investigated by Melzer et (57), showing that the hyperfine field described in the latter work decreases with Ti content (Fig. 10).…”

“…The spectrum of the spinel phase synthesized by soft chemistry (Fig. 9a) corresponds to the Mo¨ssbauer spectrum expected for a ferrimagnetic polycrystalline material with the superposition of more than two magnetic hyperfine sextets (57,58). Clear differences exist, however, from the spectrum published by Melzer et al for a titanoferrite of the same composition (58).…”

The High Temperature Properties of Tin-Doped Magnetite

“…The sharpness of the transition is consistent with the high degree of homogeneity of the sample as procedure involving three sextets (8) and the procedure where the B-sextet is split into two sextets (9). On the indicated by X-ray powder diffraction.…”

“…sition (8). The maintenance of charge balance resulting 680 Ϯ10 K. The lowering of the Curie temperature with increasing tin content is somewhat greater than that refrom the replacement of Fe 3ϩ by Sn 4ϩ is reflected in the increase in chemical isomer shift for the B 2 and C sextets corded from related titanomagnetite systems (10).…”

Maghemite in Icelandic basalts

“…The presence of such impurities will lead to deviations from the stoichiometric B/Aratio, but will also lead to substantial broadening of the M0ssbauer lines. A comparison of the MSssbauer spectra of our samples with those of samples with known (small) amounts of Ti (Tanaka and Kono, 1987) shows that the content of Ti in our samples is well below 2%. This is also in agreement with the results from measurements of Curie temperatures.…”