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Published on: September 5, 2018
CaFeO2: a new type of layered structure with iron in a distorted square planar coordination
Cédric Tassel1, José Miguel Pruneda, Naoaki Hayashi
1Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
Abstract:
CaFeO(2), a material exhibiting an unprecedented layered structure containing 3d(6) iron in a high-spin distorted square-planar coordination, is reported. The new phase, obtained through a low-temperature reduction procedure using calcium hydride, has been characterized through powder neutron diffraction, synchrotron X-ray diffraction, Mossbauer spectroscopy, XAS experiments as well as first-principles DFT calculations. The XAS spectra near the Fe-K edge for the whole solid solution (Sr(1-x)Ca(x))FeO(2) supports that iron is in a square-planar coordination for 0
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