  The ground-state magnetic phase diagram (including collinear and spiral
states) of the single-band Hubbard model for the face-centered cubic lattice
and related metal-insulator transition (MIT) are investigated within the
slave-boson approach by Kotliar and Ruckenstein. The correlation induced
electronic spectrum narrowing and a comparison with a generalized Hartree-Fock
approximation allow one to estimate the strength of correlation effects. This,
as well as the MIT scenario, depends dramatically on the ratio of the
next-nearest and nearest electron hopping integrals $t'/t$. In contrast with
metallic state, possessing strong band narrowing, insulator one is only weakly
correlated. The magnetic (Slater) scenario of MIT is found to be superior over
the Mott one. Unlike simple and body-centered cubic lattices, MIT is the first
order transition for most $t'/t$. The insulator state is type-II or type-III
antiferromagnet, and the metallic state is spin-spiral, collinear
antiferromagnet or paramagnet depending on $t'/t$. The picture of magnetic
ordering is compared with that in the standard localized-electron (Heisenberg)
model.
