Physical Properties of the Transition Metal Chalcogenide β‐FeSe

We have investigated the physical properties of a bulk sample β‐FeSe. This material has a metallic character in electrical properties with ferromagnetism from room temperature to 5 K. Magnetization shows an anomaly around 190 K and Hysteresis loop is still observed below this temperature. This magnetic behavior seems to arise from different temperature dependences of sublattice magnetization of Fe2+ and Fe3+. Namely, β‐FeSe is a typical ferrimagnet with good electrical conductivity.