ELECTRON-ION CORRELATION IN LIQUID ALUMINUM

The structure factor of liquid aluminum at 670-degrees-C has been newly determined by neutron diffraction with sufficient accuracy and compared with the structural data obtained by X-ray diffraction. A remarkable difference in these two structural informations is clearly detected and it is apparently larger than the experimental uncertainties. The ion-electron correlation function in liquid aluminum has been estimated from this difference with the help of theoretical values of the electron-electron correlation function by the Utsumi-Ichimaru scheme, and the valence electron charge distribution around an ion in liquid aluminum was obtained. The present result is found to agree well with the distribution function of valence electrons in solid aluminum using the pseudopotential method and suggests that the valence electrons in liquid aluminum would most likely behave as nearly free, although there is a minor mixing with the atomic wave function at the close vicinity of the ionic radius, corresponding to the orthogonalised plane wave.