Structural and magnetic study of the MnAs magnetocaloric compound

the temperature induced phase transition in mnas is analyzed in this work using x ray rietveld refinement. the results show the presence of the hexagonal phase (p63/mmc) at room temperature and the first-order structural-magnetic transition to the orthorhombic phase (pnma) around 318 k was followed in detail. the mnas magnetic characterization allowed to obtain the transition temperature and a maximum value of 47 j/(kg.k) for the measured magnetocaloric effect for a magnetic field variation of 5 t.