论文信息 - Syntheses, powder neutron diffraction structures and Mössbauer studies of some complex iron oxyfluorides: Sr3Fe2O6F0.87, Sr2FeO3F and Ba2InFeO5F0.68

Syntheses, powder neutron diffraction structures and Mössbauer studies of some complex iron oxyfluorides: Sr3Fe2O6F0.87, Sr2FeO3F and Ba2InFeO5F0.68

Sr2FeO3F and the novel phases Sr3Fe2O6F0.87 and Ba2InFeO5F0.68 have been prepared and their structures investigated by powder neutron diffraction methods. Sr2FeO3F crystallises with the T* modification of the K2NiF4 structure owing to oxide/fluoride ordering. Sr3Fe2O6F0.87 and Ba2InFeO5F0.68 are mixed valent phases prepared by reaction of anion deficient iron(III) materials with gaseous fluorine. Sr3Fe2O6F0.87 is a Ruddlesden–Popper type material which has been shown by Mossbauer spectroscopy to contain iron(III) and iron(V). Ba2InFeO5F0.68 is the first example of an iron oxyfluoride with a perovskite-type structure.

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