We have measured the specific heat on λ-(BEDT-TSF)2FeCl4 as a function of temperature by a thermal relaxation method to study the metal-to-insulator (MI) transition around 8K and anomalous ferroelectric-like state revealed by microwave measurements for the metallic state. The specific heat exhibits a sharp peak due to the antiferromagnetic ordering at TMI=8.3K. We have found a remarkable jump at 70K labeled as TFM. Together with the ferroelectric-like response emerging around TFM, this result confirms thermodynamically a ferroelectric-like transition at TFM in the metallic states. Furthermore, the thermal conductance of the sample may exhibit an anomaly at TFM.
- Antiferromagnitic order
- Metal-to-insulator transition
- Specific heat
- Thermal conductivity
- π-d interaction