J. Blanusa et al. / Solid State Communications 133 (2005) 157–161
161
can be correlated with the proposed description of the
exchange mechanism in rare-earth fluorides. Namely,
according to [9] magnetic properties of rare-earth fluorides
strongly depend on the balance between competing short-
range antiferromagnetic superexchange interaction and
long-range ferromagnetic dipol–dipol interaction. In case
of undiluted ErF3 compound these balance is preserved and
above magnetic critical temperature TO1 K it behaves like
common paramagnet. Magnetic dilution affects to the
greater extent the short-range interactions and consequently
long-range ferromagnetic interactions prevail. This enables
emergence of the field-induced ferromagnetic ordering in
the applied magnetic field at sufficiently low temperatures.
However, for large magnetic dilution, i.e. for xZ0.2 and 0.1
samples, long-range correlations become also ineffective
and system displays paramagnetic behavior again.
leads to the field-induced magnetic behavior of the diluted
samples with high erbium concentration, xZ0.9 and 0.7.
This behavior is in compliance with the findings made on
the HoF3 compound [9].
Acknowledgements
This work is an outcome of the joint project ‘Synthesis
and Physical Properties of Nanosize and Polycrystalline
Magnetic Materials’ financed by the Serbian Ministry of
Science and Environment and Slovenian Ministry of
Education, Science and Sport.
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