High-level ab initio electronic structure calculations of RgBe2O2 and RgBe2O2Rg (Rg = He, Ne, Ar, Kr and Xe) complexes

We investigated the rare gas binding ability of the rhombus Be2O2 molecule by high-level ab initio coupled-cluster CCSD(T) method. It was shown that Be2O2 can have a larger binding energy than a typical van der Waals interaction energy. It was also found that Be2O2 can bind two rare gas atoms where the second rare gas atom attaches with a somewhat smaller binding energy than the first atom. The calculated binding energy increases from He to Xe. This behavior is different from previously studied cases, where Ne binding energy is generally smallest among five rare gas atoms.