Experimental study of resonant photoemission in the metals V, Cr, Mn and Co

We have studied the resonant photoemission of the valence band in V, Cr, Mn and Co transition metals using synchrotron radiation excitation near the 3p ionization thresholds. The effect of the 3p - 3d interaction reaches maximum strength in Cr and Mn. On the other hand, the contribution related to the atomic Fano resonance goes to a minimum in Mn and increases rapidly on moving to Co. This behaviour is also reflected in the values of the effective Coulomb hole - hole interaction which we have calculated from experimental spectra. Furthermore, we have investigated when the Auger transition appears in the vicinity of the 3p ionization thresholds. Our results reveal that V, Cr and Co do not show the so-called subthreshold Auger emission whereas it can possibly be observed in Mn. However, we attribute the unusual appearance of the Auger peak to the wide valence band of Mn rather than the 3p - 3d resonance.