  Magneto-structural properties of films of diluted ferromagnetic alloys
Ni$_x$Cu$_{1-x}$ in the concentration range $0.7 < x < 1.0$ are studied
experimentally. Films deposited by magnetron sputtering show partial phase
separation, as evidenced by structural analysis and ferromagnetic resonance
measurements. The phase diagram of the Ni$_x$Cu$_{1-x}$ bulk system is obtained
using numerical theoretical analysis of the electronic structure, taking into
account the inter-atomic exchange interactions. The results confirm the
experimentally found partial phase separation, explain it as magnetic in
origin, and indicate an additional metastable region connected with the
ferromagnetic transition in the system.
