Origin of magnetic properties and martensitic transformation of Ni-Mn-In magnetic shape memory alloys

The nature of unique magnetic properties and martensitic transformation of Ni2Mn1+xIn1-x shape memory alloy has been revealed by first-principles calculations. The uncommon magnetic properties occurring upon martensitic transformation are originated from the change of Mn-Mn interatomic distances. The critical value of Mn-Mn interatomic distance corresponding to the change of magnetic interactions has been determined. A decrease of the intensity of Ni 3d states at the Fermi level upon martensitic transformation has been observed for x = 0.5. Moreover, the Ni 3d-Mn 3d hybridization plays an important role in establishing the magnetic properties and driving the martensitic transformation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3697637]