This experiment aims to analyse the magnetic response of nanoparticles of a rare earth-based alloy of NdCu2. The study is fundamental as it may establish the magnetic correlations among nanoparticles of a magnetic alloy. The magnetic nanoparticles are routinely used for biomedical applications (Fe-Oxides). The advantage of NdCu2 nanoparticles is that they constitute a case example and the results can be extended to those Fe-oxide nanoparticles. The magnetic structure is antiferromagnetic NdCu2 in bulk but, when it is milled and nanoparticles are then produced, the magnetic core retains such a magnetic structure but the shell is modified giving rise to magnetic disorder. The overall nanostructure is what we want to disclose.