Computational study of the effective three-ion interaction potentials in   liquid metals with high density of electron gas
  Based on the many-body theory of metals in the third order of the perturbation expansion in electron-ion interaction pseudopotential, the potentials of pair and three-ion interactions are calculated in liquid lead, aluminium and beryllium at their melting temperatures. The reducible and irreducible three-ion interactions have an attractive nature on distances approximately equal to an average distance between ions in metals. It results in the shortening of average interatomic distance in an equilibrium state of metal. The potential landscapes created by a pair of fixed ions relative to the third ion are constructed. It is shown that with increasing of an electronic density the contribution as reducible, that and irreducible three-ion interaction is increased. It is shown also that the influence of reducible three-ion interaction on a potential landscape in a cluster of three ions is considerably larger than influence of irreducible three-ion interaction. 
E. V. Vasiliu