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.
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