State-selective production of vibrationally excited NO2+ by double-resonant photoionization

Two-color, two-photon resonant, three-photon ionization, and high-resolution photoelectron spectroscopy are combined to characterize the photoionization dynamics of the 3psigma (2)Sigma(u)(+) electronic state of NO2. Direct photoionization of selected vibrational levels of the NO2 3psigma (2)Sigma(u)(+) state shows a strong propensity to preserve the vibrational quantum numbers of the intermediate state. Efficient methods for producing NO2+ X (1)Sigma(u)(+) (000), (010), (100), and (001) with over 95% purity are discussed. This approach is expected to be applicable u to the study of the mode dependence of the effects of vibrational excitation in ion-molecule reactions involving NO2+.