  The magnetic moments and magnetic anisotropy energy (MAE) of CoRh alloy
nanoparticles are determined experimentally and theoretically. Non-trivial
correlations between chemical order, magnetic order and MAE are revealed. A
remarkable non-monotonous dependence of the MAE as a function of composition
and chemical order is observed that opens novel possibilities of tuning the
magnetic properties of nanoalloys. The observations are successfully compared
and analyzed with our electronic calculations. In this way we clearly
demonstrate that the induced 4d moments and the 3d-4d interfaces are the key
parameters controlling the magneto-anisotropic behavior.
