Pair potential and structure factors of liquid alkali metals

Measured structure factors of liquid alkali metals are examined in the framework of screened pair potential theory. Information on the main attractive well in the effective pair potential is obtained from the structural data by an approximate method stemming from an optimized random-phase treatment of the indirect ion-ion attraction. The small-angle scattering region is then examined in considerable detail, with special attention to the possibility of a linear term in a series expansion of the structure factor at very small momentum transfer. No linear term of the magnitude reported in recent X-ray diffraction experiments is found in the present theoretical framework