First principles study of the ground and excited states of FeO, FeO+, and FeO-

Through a variety of highly correlated methods combined with large basis sets we have studied the electronic structure of FeO, FeO+, and FeO-. In particular, we have constructed complete potential energy curves for 48, 24, and 4 states for the FeO, FeO+, and FeO- species, respectively, at the multireference level of theory. For all states examined we report energetics, common spectroscopic parameters, and dipole moments. Overall our results are in good agreement with experiment, but we have encountered as well interesting differences between experiment and theory deserving further investigation. (C) 2011 American Institute of Physics. [doi:10.1063/1.3598529]