| To identify the relevant electronic systems and their interactions we have determined the magnetic and superconducting order parameters and electronic phase diagrams in several classes of iron pnictide superconductors by μSR and Mössbauer spectroscopy. The results prove an important role of the structural distortion for the SDW magnetism and reveal two gap multiband superconductivity. We examined the interplay of iron and rare earth magnetic order in ReO1-xFxFeAs. The undoped compounds show different magnetic coupling strength of the rare earth ion to the antiferromagnetic iron layers ranging from independent order to strong polarization of the rare earth moments by the ordered iron. Finally, we present recent studies on (Ca,Sr,Ba,Eu)Fe2As2 and (Fe2As2)(Sr4T2O6) based pnictide superconductors. |
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