C. Hunt et al., APPLIED-FIELD MOSSBAUER STUDIES OF THE IRON STORAGE PROTEINS FERRITINAND HEMOSIDERIN, Hyperfine interactions, 91(1-4), 1994, pp. 821-826
Applied field Mossbauer spectra obtained from ferritin and haemosideri
n have been fitted using a spin-Hamiltonian model, to determine the ef
fect of the applied field on the direction of the iron magnetic moment
s. The results of these fits indicate that the ordering of magnetic mo
ments within the ferrihydrite core of these proteins is antiferromagne
tic. The values of the anisotropy field obtained from these fits corre
spond to much higher values of the superparamagnetic blocking temperat
ures than those actually observed. This anomaly has implications for o
ur understanding of the superparamagnetic relaxation processes in thes
e materials.