Figure 4: Valence band of (a) TPP multilayer on iron or iron silicide onto Si. Monolayer of Fe-TPP on (b) Fe3Si, (c) Fe onto Si after annealing at 550 K. (d) is difference spectra and (e) Fe3Si on Si. The shift = 0.99 eV is shown here in spectra (d) and (e). Under the experimental spectra, we report the expected contribution of HOMO states and represented by A, B, C, and D respectively.