The first-principles study of martensitic transformations in MnMe (Me = Rh, Pd) alloys at low temperatures

► Predicted phase stability trends due to structural energy differences are confirmed. ► The softening of (C11 - C12)/2 triggers the cubic to tetragonal phase transformation. ► Debye temperature, anisotropy and Poisson's ratio are first assessed. ► Obtained phonon curves and DOS at EF reveal that AFM-L10 is most stable.