TY - JOUR
TI - Magnetic and epr studies of α-, β-, and γ-fe2wo6 phases at low temperatures
AU - Guskos, N.
AU - Sadlowski, L.
AU - Typek, J.
AU - Likodimos, V.
AU - Gamari-Seale, H.
AU - Bojanowski, B.
AU - Wabia, M.
AU - Walczak, J.
AU - Rychlowska-Himmel, I.
JO - Journal of Solid State Chemistry
PY - 1995
VL - 120
TODO - 2
SP - 216-222
PB - 
SN - 0022-4596, 1095-726X
TODO - 10.1006/jssc.1995.1401
TODO - null
TODO - The polymorphic modifications α-, β-, and γ-Fe2WO6 of the iron tungstate system were studied by means of magnetic susceptibility and EPR measurements at low temperatures. Both methods revealed a significant paramagnetic contribution, probably resulting from local distortions of the antiferromagnetic bulk structure induced by a disturbed cation ordering or the presence of Fe2+ ions. The magnetic susceptibility revealed a peak at ∼260 K for all samples which can be related with an AF phase transition. The EPR spectra comprised the contribution of various isolated paramagnetic iron centers, one arising from high-spin Fe3+ ions in rhombic crystal field symmetry with E/D ≈ 1/3 and D ≈ 0.22 cm-1, an anisotropic EPR signal consistent with an S = 3/2 ground state with large zero-field splitting, and a dominant component in the g ≈ 2 region presumably arising from an S = 1/2; spin state. The latter spectra were tentatively attributed to the formation of multi-iron clusters, one of them invoking the presence of Fe2+ ions as well. For the βFe2WO6 phase an additional EPR spectrum was observed, which probably results from high-spin Fe3+ ions in a weak crystal field. © 1995 Academic Press. All rights reserved.
ER -