Potential energy surfaces for interactions of H 2O with H 2, N 2 and O 2: A hyperspherical harmonics representation, and a minimal model for the H 2O-rare-gas-atom systems

A representation, based on the hyperspherical harmonics expansion, is given for the potential energy surfaces for the interactions of H2O with H2, N2 and O2. The interaction energies have been obtained by extensive ab initio calculations at the CCSD(T)/aug-cc-pVTZ level. The results are compared with available experimental information and with previous theoretical data at different calculation levels, based on previous work carried out in our and in others laboratories. Data are also assessed with reference to a phenomenological description specific for this kind of complexes. These analytical representations of the potential energy surfaces can be used in molecular dynamics, and are particularly suited for classical and quantum scattering studies. A minimal model representing the interaction of H2O with rare gas atoms is also presented in this article.