A combined variational and perturbational study on the vibrational spectrum of P2F4

The structure and vibrational spectrum of tetrafluorodiphosphine, P2F4, were studied by calculating large fractions of the multidimensional potential energy surface at the coupled-cluster level. Vibrational corrections to the geometrical parameters were accounted for by calculating the vibrational wave function using configuration interaction theory (VCI). Fundamental modes, first vibrational overtones and low lying combination bands were computed at the same level and were compared with results from vibrational perturbation theory. A comparison with experimental results is provided.