Magnetic and electronic properties of CaFeO2Cl

Rendenbach, Bettina; Klenner, Steffen; Poettgen, Rainer und Johrendt, Dirk (2020): Magnetic and electronic properties of CaFeO2Cl. In: Zeitschrift für Naturforschung Section B-A Journal of Chemical Sciences, Bd. 75: S. 105-110

Abstract

CaFeO2Cl is a unique exception in the family of the iron oxyhalides. Its crystal structure is not related to the Ruddlesden-Popper phases as known for the other members, but contains layers of edge-sharing FeO2/2O3/3 pyramids without Fe-Cl contacts. The iron atoms form a distorted honeycomb substructure. Magnetization measurements on single crystals show an unexpected weak anisotropy and indicate antiferromagnetic ordering of the iron magnetic moments already at room temperature. Fe-57 Mossbauer spectra confirm the trivalent oxidation state of iron and the presence of magnetic order. DFT calculations using the LDA + U approach support a Mott-insulating antiferromagnetic ground state and indicate a Neel-type ordered antiferromagnetic state in the honeycomb layer. The band gap from optical measurements is 1.3 eV and agrees with the red-brown colour as well as with the theoretical calculations.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Chemie und Pharmazie > Department Chemie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 0932-0776
• Sprache: Englisch