Spinel 결정내에서의 초교환 상호작용에 관한 연구

A Study on the Superexchange Interactions of Spinel Crystals

  For studies on the magnetic properties of spinel crystals, both microscopic measurements by the M？ssbauer spectra method and macroscopic measurements by the magnetic susceptibility method have been made on a number of compounds in the family Fe<SUB>x</SUB>Cu<SUB>1-x</SUB> Rh₂Se₄.   The Fe<SUB>x</SUB>Cu<SUB>1-x</SUB> Rh₂Se₄ were prepared by the direct composition method from the X-ray diffraction studies lattics parameters have been shown with Vegad law.   The M？ssbauer spectra were analyzed by the Non linear regression least square fitting method using a computer.   Temperature dependence of inverse magnetic susceptibility show that the values of θ indicate -150K and -182Kfor Fe<SUB>0.1</SUB> Cu<SUB>0.9</SUB> Re₂ Se₄ and FeRh₂Se₄ respectively.   Spinel crystals Fe<SUB>x</SUB>Cu<SUB>1-x</SUB> Rh₂Se₄ are antiferromagnetic exhibiting negative superexchange interaction.   The isomer shift indicate that Fe ion tend toward Fe？³ and Fe？² values respectively.