Ab initio study of the electronic structure of zinc oxide and its ions, ZnO(0,+/-). Ground and excited states.

The species ZnO and ZnO(+/-) have been studied by variational multireference and coupled-cluster [RCCSD(T)] methods employing augmented basis sets of quintuple cardinality. Full potential energy curves are reported for 13, 10, and 2 bound states of ZnO, ZnO(+), and ZnO(-), respectively. All our results are in excellent agreement with existing experimental findings.