%0 Journal Article
%T Structure and physical properties of new layered iron oxychalcogenide BaFe2OSe2
%A Hechang Lei
%A Hyejin Ryu
%A John Warren
%A A. I. Frenkel
%A V. Ivanovski
%A B. Cekic
%A C. Petrovic
%J Physics
%D 2012
%I arXiv
%R 10.1103/PhysRevB.86.195133
%X We have successfully synthesized a new layered iron oxychalcogenide BaFe2OSe2 single crystal. This compound is built up of Ba and Fe-Se(O) layers alternatively stacked along the c-axis. The Fe-Se(O) layers contain double chains of edge-shared Fe-Se(O) tetrahedra that propagate along the b-axis and are bridged by oxygen along the a-axis. Physical property measurements indicate that BaFe2OSe2 is a semiconductor without the Curie-Weiss behavior up to 350 K. There is a possible long range antiferromagnetic (AFM) transition at 240 K, corresponding to the peak in specific heat measurement and two glassy transitions at 115 K and 43 K. The magnetic entropy up to 300 K is much smaller than the expected value for Fe2+ in tetrahedral crystal fields and Mosbauer spectrum indicates that long range magnetic order is unlikely at 294 K. Both results suggest that a short range magnetic correlations exist above the room temperature.
%U http://arxiv.org/abs/1206.5788v1