New layered perovskites in the SrRuO system: A transmission electron microscope study

The new perovskite-related layered phase Sr3Ru2O7 has been prepared and characterised: electron microscopy and powder X-ray diffraction shows it to be isostructural with Sr3Ti2O7. This n = 1 structure represents the upper limit of layer thickness for well-ordered material in the homologous series which includes Sr2RuO4 and SrRuO3, the n = 0 and n = ∞ end-members. Preparations between Sr3Ru2O7 and SrRuO3 are highly disordered, comprising a wide variety of different layer-thicknesses. © 1991.