We follow the step by step progression of events while approaching Curie temperature TC from below using 57Co substituent as microprobe in an emission Mössbauer study combined with resistivity measurements. In the temperature range 0.33 < T/TC ≤ 1, the material consists of a mixture of ferromagnetic and paramagnetic regions within the same matrix. An increase of the amount of paramagnetic fraction is accompanied by a decrease in electron delocalization in the ferromagnetic regions. At T ≥ TC , the electrons are localized to neighboring Mn4+/Mn3+ pairs only, in about 46% of the paramagnetic species. The strength with which Mn atoms are bound to the neighbors also decreases progressively and rather steeply in the range 0.65 ≤ T/TC = 1. Zero field resistivity, ρ0, follows linearly with the amount of paramagnetic phase in the range 0.65 ≤ T/TC ≤ 1 and still show metal-like behavior up to T/TC ≈ 1.03.
|Number of pages||6|
|Journal||Fizika Nizkikh Temperatur (Kharkov)|
|Publication status||Published - 1997 Dec 1|
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)