  We report a theoretical study on resonant x-ray emission spectra (RXES) in
the whole energy region of the Mn $L_{2,3}$ white lines for three prototypical
Mn/Ag(001) systems: (i) a Mn impurity in Ag, (ii) an adsorbed Mn monolayer on
Ag, and (iii) a thick Mn film. The calculated RXES spectra depend strongly on
the excitation energy. At $L_3$ excitation, the spectra of all three systems
are dominated by the elastic peak. For excitation energies around $L_2$, and
between $L_3$ and $L_2$, however, most of the spectral weight comes from
inelastic x-ray scattering. The line shape of these inelastic ``satellite''
structures changes considerably between the three considered Mn/Ag systems, a
fact that may be attributed to changes in the bonding nature of the Mn-$d$
orbitals. The system-dependence of the RXES spectrum is thus found to be much
stronger than that of the corresponding absorption spectrum. Our results
suggest that RXES in the Mn $L_{2,3}$ region may be used as a sensitive probe
of the local environment of Mn atoms.
