Anomalous Thermal Expansion and Specific Heat of the Ferromagnetic Compound Au₄Mn

Abstract

The results of measurement of thermal expansion and specific heat are presented for the ferromagnetic compound Au₄Mn in the temperature range from room temperature to 430°K which includes the Curie point of this compound (T_c=371°K). Anomalous specific heat at the Curie point is estimated to be ΔC_p=1 cal/mol·deg. Anomalous thermal expansion is found to be anisotropic, Δa⁄a<0 and Δc⁄c>0. These results are discussed in connection with the pressure effect to the magnetization and the Curie point.