This paper presents the first example of distinguishing various phases differing in the valence state of iron in the solid state reduction of Fe(VI) to Fe(III) oxides at 235 °C using hyperfine parameters, isomer shift and hyperfine magnetic field, obtained from nuclear forward scattering of synchrotron radiation (NFS). The NFS technique enables a fast data accumulation resulting in high time resolution of in situ experiments. The results suggest a reaction mechanism, involving Fe(V) and Fe(IV) species, in the thermal decomposition of K2FeO4 to KFeO2.
Machala, L .; Prochazka, V.; Miglierini, M.; Sharma, V. K.; Marusak, Z.; Wille, H. C.; Zboril, R. Direct evidence of Fe(V) and Fe(IV) intermediates during reduction of Fe(VI) to Fe(III): a nuclear forward scattering of synchrotron radiation approach. Phys. Chem. Chem. Phys. 2015, 17, 21787-21790.