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Fe ion doping effect on electrical and magnetic properties of La0.7Ca0.3Mn1-xFexO3 x = 0.0 to 1.0

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 نشر من قبل Veer Awana Dr
 تاريخ النشر 2010
  مجال البحث فيزياء
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Here we report the structural, electrical and magnetic properties of Fe doped La0.7Ca0.3Mn1-xFexO3 with x = 0.0 to 1.0 prepared by conventional solid state reaction method. Simulated data on XRD shows an increase in volume with an increase in Fe ion concentration. XPS supports that Fe3+ ions directly substitute Mn3+ ions. Shifting towards lower wave-number and symmetric IR band structure confirms increase in volume and homogeneous distribution of Fe ions. Fe ion doesnt contribute in double-exchange (DE) conduction mechanism due to its stable half filled 3d orbital. The presence of Fe3+ ions encourages anti-ferromagnetism (AFM) generated by super-exchange interaction and suppress insulator-metal transition temperature (TIM). Magnetic measurements show the existence of magnetic polarons supported by increase in volume of unit cell and deviation from Curie-Weiss law.



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