TOWARDS RELIABLE MODELING OF LARGE CLUSTERS - ON THE OVERALL ACCURACYOF THE DIATOMICS-IN-MOLECULE METHOD FOR RARE-GAS CLUSTER IONS

The accuracy of the diatomics-in-molecules (DIM) method is examined fo r the case of rare gas ionic clusters through a series of careful cali bration calculations. Ab initio potential energy functions for Rg(3)() and Rg(4)(+) (Rg = He, Ne, Ar) are 3 compared with the DIM model, ta king diatomic potentials computed at exactly the same level of ab init io theory as input. For Ne-n(+) and Ar-n(+) agreement is satisfactory (in most important regions within 0.05 eV), whereas for He-n(+), large deviations occur.