Nonadditive interactions and the relative stability of neutral and anionic silver clusters

We discuss the physical nature of nonadditivity in many‐particle systems and the methods of calculations of nonadditive contributions to the interaction energy. For neutral clusters, a closed recurrence formula which expresses the energy of m‐body interactions through the energies of 2‐, 3‐, and (m – 1)‐body ones is obtained. The general approach for calculation of the nonadditive contribution in the interaction energy of charged systems is developed. The comparative calculation of anionic and neutral silver clusters shows that the geometry of the most stable anionic clusters is established mainly by the additive forces. The stability of neutral silver clusters is determined by the competition of attractive additive forces and repulsive nonadditive ones.