A critical discussion of calculated modulated structures , Fermi surface nesting and phonon softening in magnetic shape memory alloys Ni 2 Mn ( Ga , Ge , Al ) and Co 2 Mn ( Ga , Ge )
نویسندگان
چکیده
A series of first principles calculations have been carried out in order to discuss electronic structure, phonon dynamics, structural instabilities and the nature of martensitic transformations of the Heusler alloys Ni2Mn(Ga, Ge, Al) and Co2Mn(Ga, Ge). The calculations show that besides electronic pecularities like Fermi–surface nesting, hybridizing optical and acoustic phonon modes are important for the stabilization of the modulated martensitic structures.
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