Ab initio study of water hexamer anions

The wet electron - an electron interacting with a small cluster of water molecules - is a simple yet fundamental system for understanding the behavior of electrons in complex molecular systems. A comprehensive post Hartree-Fock ab initio study is performed on the wet electron in various water hexamer clusters including the low-lying energy conformers of the neutral species. The predicted geometries, total energies, photoemission ionization energies, electronic structure and orbital character of the excess electron in ground and excited states are discussed. To understand the behavior of the excess electron in the clusters, the s-orbital-like character of the HOMOs and the p-orbital-like character of the LUMOs are investigated.