Specific heat of MnCoGe type compounds at martensitic phase transitions

Abstract

The X-ray diffraction and specific heat measurements have been performed for the ferromagnetic compounds (MnCo)1-xGe within the concentration range 0.02 ≤ x ≤ 0.035. The compounds possess the hexagonal Ni 2In-type structure at elevated temperatures, while for the composition with x = 0.02 and 0.03 a spontaneous martensitic-type transition to the orthorhombic TiNiSi-type phase occurs at 283 and 221 K, respectively. We studied the entropy changes associated with the first-order structural transition and estimated the changes in magnetic, lattice, electronic entropies. © (2012) Trans Tech Publications.