Spin state and magnetic interactions of Co3+ in PrBaCo2O5.50

Abstract We have studied the magnetic and structural properties of PrBaCo 2 O 5.50 using neutron and synchrotron techniques between 10 and 425 K. A unique structural transition has been detected in this temperature range. The changes observed in Co–O bond lengths across the metal–insulator transition confirm the spin state change of octahedral Co ions with R = Pr . We have also studied the sequence of magnetic structures appearing in this compound.