Strong correlation satellites in core level photoemission from Mn in the monolayer range on Ag(001)

We observe a complex shape of the Mn2p core level photoemission spectra for Mn in structures of reduced dimensionality such as an ideal monolayer on A g(001). The Mn2p(3/2) and Mn2p(1/2) spectral intensity is found to split in to doublets with separation about 4 and 5 eV, respectively. The data indica te an interpretation in terms of a poorly screened and a well screened fina l state of the Mn with a core hole. In the monolayer range these two final states have comparable intensities and dominant contributions from atomic 2 p(5)3d(5) and 2p(5)3d(6) configurations, respectively. Their intensity rati o is found to be extremely sensitive to the Mn atomic environment and direc tly reflects the degree of the Mn3d localization, electron correlation and reduction in charge fluctuations. Additional fine structure is clearly visi ble in high-resolution data for both final state 3d electrons counts and ca n be assigned to direct and exchange Coulomb interactions of the unfilled c ore and 3d shells. Slow 3d-charge fluctuations also result in a remarkable three-peak structure of the Mn3s line. (C) 1999 Elsevier Science B.V. All r ights reserved.