My thesis dealt with perovskites of the general type A(Fe,Rh)O₃, containing Bi³⁺, La³⁺, Ca²⁺ and Sr²⁺ on the A-position. A main interest was the search for new materials, possibly active for the exhaust treatment in lean-burn engines. However, the thesis mainly covers classical solid state chemistry of these materials. The catalytic results were to be kept confidential.

A survey of the system Bi - Fe - Rh - O had already been subject to my diploma thesis and I extended research here. A new composition, BiFe_0.5Rh_0.5O₃, has been found exhibiting spin-glass behaviour and a relatively high degree of long range order below the spin-freezing temperature (ca. 250 K). These results have been worked out in a collaboration with the group of G. Filoti and M. Rosenberg. The M–ssbauer-part of the work was published.
The freezing temperature could be confirmed by neutron experiments at HMI. However, due to an unknown impurity phase, Rietveld-refinements of the neutron data are still not completed.

First results in the field of simple perovskites containing rhodium have also been reported. In the system Sr - Rh - O only K₂NiF₄-type Sr₂RhO₄ and Sr₄RhO₆(Sr₄PtO₆- or K₄CdCl₆-type) were known by that time. We have been able to stabilize a phase of general composition SrRhO_2.77 and by that time we suggested to deal with a mixture that contains a 9R rhombohedral polytype among others. These results finally led to the interest of continuing research on these phases. Go on reading about this in the postdoc section.