A Layered Double Perovskite Ca2FeMnO6 with Unusually High Valence Fe4+ Obtained by Low-Temperature Topotactic Oxidation
- Resource Type
- Journal Article
- Authors
- Masaichiro MIZUMAKI; Noriya ICHIKAWA; Takashi SAITO; Yoshiteru HOSAKA; Yuichi SHIMAKAWA
- Source
- Journal of the Japan Society of Powder and Powder Metallurgy. 2016, 63(7):605
- Subject
- perovskite structure oxide
topotactic oxidation
two-dimensional layered arrangement
unusually high valence ion
- Language
- English
- ISSN
- 0532-8799
1880-9014
A new double perovskite Ca2FeMnO6 with a layered arrangement of Mn4+ and the unusually high valence Fe4+ was obtained by oxidizing the brownmillerite Ca2FeMnO5 with ozone at 200 °C. The low-temperature topotactic reaction kept the layered cation arrangement of the brownmillerite but oxidized Mn3+ to Mn4+ and Fe3+ to Fe4+. The crystal structure with a P21/c space group was analyzed with the synchrotron X-ray diffraction data. The changes in the valence states of Fe and Mn were confirmed by bond valence sum calculations, X-ray absorption spectroscopy, and Mössbauer spectra measurements.