physica status solidi (RRL) – Rapid Research Letters

This study reports on the physical properties of Ba2CoO4 single crystals grown in a high pressure mirror furnace at oxygen pressures of 20 bar. Direction dependent magnetic susceptibility measurements on the single crystals below TN≈25 K reveal a spin direction which is parallel to the crystallographic a-axis. Therefore, the spin structure of Ba2CoO4 has been re-analyzed and a different magnetic structure with magnetic moments pointing mainly in a-direction is proposed which reconciles neutron, µSR, and magnetic susceptibility measurements