Influence of local structure on magnetic properties of Layered Cobaltites PrBaCo_2O{5+\delta}, \delta > 0.5

The effect of local structure on the magnetic and transport properties of the layered perovskites has been investigated. The samples PrBaCo${}_2$O${}_{5+\delta }$, ($\delta$ = 0.80 and 0.67) though crystallize in the same 112 type tetragonal structure have different magnetic ground states. Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy has been employed to explain the changes in magnetic interactions based on the rotation and tilting of CoO polyhedra in these oxygen rich double perovskites.