Crystallographic and Magnetic Properties of Nanocrystalline Cobalt Ferrite Particles

  • Yangkyu Ahn (Department of chemistry, Konyang University, Nonsan, Department of Chemistry, KAIST) ;
  • Eun Jung Choi (Department of Physics, Konyang University, Nonsan) ;
  • Sehun Kim (Department of Chemistry, KAIST)
  • Published : 1999.09.01

Abstract

Ultrafine cobalt ferrite particles have been synthesized using a microemulsion method. All peaks of X-ray diffranction patterns are fairly broad but correspond to a cubic spinel structure with the lattice constant 8.39$\AA$. The coercivity measureed at 5K is 15.1 kOe. The maximal magnetization measured at 5 and 300 K are 13.2 and 10.7 emu/g, respectively. The particles behave ferrimagnetically at 5 K but superparamagnetically at 300K. Superparamagnetic behavior of the particles at room temperature was confirmed by the conincidence of the M vs. H/T at different temperatures and the Mossbauer spectrum.

Keywords

References

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