Effect of Be additions on the electronic density of states of icosahedral Al-Cu-Fe compounds

Using the Soft X-ray Emission Spectroscopy technique, we have investigated the electronic structure of a series of Al-Cu-Fe compounds in which Al atoms have been substituted by Be atoms. Changes in the shape of Al 3s,d spectral curves are clearly visible in the energy region extending over 2 e V below the Fermi level. Calculation of the moments of orders I and 2 of the partial electronic distributions show that there is a slight decrease of the contribution of Fe 3d states to the total energy of the system and that there are changes in Fe hybridisation that tend to enhance the localised character of the Al states in the vicinity of the Fermi level. Yet, the shape of the pseudo-gap does not change.