Alloying effect on the electronic structure of aluminium

The influence of a number of alloying elements on the electronic structure of aluminium has been investigated by the DV-X alpha cluster method. The energy level structure was modified remarkably by alloying. For transition metals, for instance, this modification was mainly due to the appearance of the virtual bound state of d electrons near the Fermi energy level. Except for a few elements, the ionicities of alloying elements change monotonically following the electronegativity. The bond order between atoms largely depends on the alloying elements, while the activation energy for the 3d impurity diffusion in aluminium can be related to the calculated bond order. An increment of the residual resistivity, due to the 3d impurities doped into aluminium, also correlates well with the virtual bound state density at the Fermi energy level. In addition, it is shown from calculations that Mn and Cr are probably the magnetic impurities in aluminium.