The importance of transition metal centers as catalysts for selective trans formations of small molecules into useful chemicals has prompted exten sive studies in the condensed phase. In the last decade or so , chemical analogues to these processes have also been investigated in the gas phase. The promise of the gas phase research is that more quantitative infor mation regarding the dynamics, kinetics, and thermochemistry of these processes can be obtained in a more controlled environment. A particularly active component of this gas phase research is the chemistry of atomic transition metal ions, which are conveniently studied by several types of mass spectrometric techniques (1-7). Although the relationship between this gas phase endeavor and condensed phase organometallic chemistry is still evolving , one area in which gas phase studies have contributed some insight into the reactivity at transition metal centers concerns the influence of the electronic state (8a). The abundance of low-lying electronic statcs is one of the features of transition metals that is integral to their ability to catalyze chemistry , since it allows a metal center to be a versatile reaction template in which many different types of species can bond and subsequently react. Unfortunately, this same feature makes it difficult to generate transition metals (atoms, ions , or complexes) in specific electronic states. Table I shows the extent of the problem for the first row transition metal ions. Since ion generation