  An exchange correlation energy functional involving fractional power of the
one-body reduced density matrix [Phys. Rev. B {\bf 78}, 201103 (2008)] is
applied to finite systems and to the homogeneous electron gas. The performance
of the functional is assessed for the correlation and atomization energies of
the molecules contained in the G2 set and for the correlation energy of the
homogeneous electron gas. High accuracy is found for these two very different
types of systems.
