X-ray band spectra of CoAl

The valence band K and L emissions of Co and Al in the intermetallic compound CoAl have been calculated by using the site- and symmetry-projected densities of states obtained from a self-consistent symmetrised APW band calculation. The results are compared with K emission spectra measured with a two-crystal X-ray spectrometer and L emission spectra measured previously. The measured K spectra are reproduced well by the calculations. On the other hand, the experimental Co L emission band is considerably broader than indicated by the calculation. Also in the Al L emission the agreement is only fair. The position of the d states is found experimentally in this case to deviate by 0.5 eV from the predicted position.