PHILOSOPHICAL MAGAZINE, vol.89, pp.2093-2109, 2009 (SCI-Expanded)
We study the structural and magnetic properties of Heusler based Ni50Mn50-xSbx in the composition range 5.0 <= x <= 25.0. The cubic phase is preserved in the range 17.0 <= x <= 25.0, and the presence of martensitic transformations are found in alloys with x <= 15.0. In a critical composition range 12.5 <= x <= 10.0, the magnetic coupling in both austenitic and martensitic phases is paramagnetic, however, the presence of antiferromagnetic short-range correlations is observed in both phases. We discuss the consequences of these correlations on the behavior of the magnetic moment with respect to electronic properties.