Abstract
Neutron diffraction studies have been carried out on a single crystal of oxygen-deficient perovskite NdBaCo2O5:5 in the temperature (T) range between 7K and 320 K. We have found a magnetic transition at Tc ~ 170 K, and a rapid change of the intensities of several reflections at Tc ~ 30 K. The magnetic structures have been analyzed at 7K (< Tc) and 40K (Tc < T < Tc). Non-collinear magnetic structures, which are based on the G-type antiferromagnetic structure, are proposed at these temperatures. In the T region between T* and Tc, Co3+ ions of CoO6 octahedra are in the intermediate spin state, and those of CoO5 pyramids are in the high spin state. In the region of T < Tc, the magnitude of the Co3 spins in the octahedra decreases gradually as T decreases, suggesting that the spin state approaches the low spin state. It is pointed out that the spin state of Co ions depends on the local structure around them.
Original language | English |
---|---|
Pages (from-to) | 2857-2862 |
Number of pages | 6 |
Journal | journal of the physical society of japan |
Volume | 73 |
Issue number | 10 |
DOIs | |
Publication status | Published - 2004 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)