The weird, but sometimes wonderful, world of managante perovskites

Perovskite manganites with the general formula Sr1-xPrxMn03, have been prepared for compositions x = 0.1-0.6 in steps as fine as 0.025. These oxides have been extensively studied using a combination of magnetic susceptibility, Synchrotron¬Xray and Neutron powder diffraction and X-ray Absorption spectroscopy. The resulting body of information reveals numerous examples of unusual behavior, reflecting coupling between the spin, orbital and lattice degrees of freedom. At room temperature the the structures evolve as the Pr content increase due to changes in the tilting of the corner shared Mn06 octahedra. However examination of the structures reveals a complex evolution in the distortion of the octahedra reflecting the conflicting requirements of the Jahn-Teller like orbital ordering and the octahedral tilting. These conflicts results in unusual temperature dependence of the structures.