Abstract
The Fe Mössbauer spectroscopy of mononuclear [Fe(II)(isoxazole)](ClO) has been studied to reveal the thermal spin crossover of Fe(II) between low-spin (S = 0) and high-spin (S = 2) states. Temperaturedependent spin transition curves have been constructed with the least-square fitted data obtained from the Mössbauer spectra measured at various temperatures between 84 and 270 K during a cooling and heating cycle. This compound exhibits an unusual temperature-dependent spin transition behaviour with T(?) = 223 and T(?) = 213 K occurring in the reverse order in comparison to those observed in SQUID observation and many other spin transition compounds. The compound has three high-spin Fe(II) sites at the highest temperature of study of which two undergo spin transitions. The compound seems to undergo a structural phase transition around the spin transition temperature, which plays a significant role in the spin crossover behaviour as well as the magnetic properties of the compound at temperatures below T. The present study reveals an increase in high-spin fraction upon heating in the temperature range below T, and an explanation is provided.
| Original language | English |
|---|---|
| Pages (from-to) | 2713-2718 |
| Number of pages | 6 |
| Journal | Journal of Physics and Chemistry of Solids |
| Volume | 69 |
| Issue number | 11 |
| Early online date | 3 Jul 2008 |
| DOIs | |
| Publication status | Published - Nov 2008 |
Keywords
- inorganic compounds
- Mössbauer spectroscopy
- magnetic properties
- phase transitions