MAGNETIC MANGANESE OXIDES AS A COMPOSITE IN ORGANIC MATRICES

Composite materials were synthesized that show spontaneous magnetizati on with well-defined hysteresis loops below 40 K. Their composition wa s characterized by chemical elementary analysis, wide angle X-ray diff raction, transmission electron microscopy, energy dispersive X-ray spe ctroscopy, selected area diffraction and electron energy loss spectros copy. The magnetic properties were analysed by SQUID magnetometry, alt ernating current susceptibility, specific heat measurement and electro n spin resonance. In these composites use is made of the exchange inte raction in manganese oxide based inorganic portions incorporated in an amorphous organic phase.