Carbon Dioxide and Water Activation by Niobium Trioxide Anions in the Gas Phase.

Transition metals are important in various industrial applications including catalysis. Due to the current concentration of CO 2 in the atmosphere, various ways for its capture and utilization are investigated. Here, we study the activation of CO 2 and H 2 O at [NbO 3 ] - in the gas phase using a combination of infrared multiple photon dissociation spectroscopy and density functional theory calculations. In the experiments, Fourier-transform ion cyclotron resonance mass spectrometry is combined with tunable IR laser light provided by the intracavity free-electron laser FELICE or optical parametric oscillator-based table-top laser systems. We present spectra of [NbO 3 ] - , [NbO 2 (OH) 2 ] - , [NbO 2 (OH) 2 ] - (H 2 O) and [NbO(OH) 2 (CO 3 )] - in the 240-4000 cm -1 range. The measured spectra and observed dissociation channels together with quantum chemical calculations confirm that upon interaction with a water molecule, [NbO 3 ] - is transformed to [NbO 2 (OH) 2 ] - via a barrierless reaction. Reaction of this product with CO 2 leads to [NbO(OH) 2 (CO 3 )] - with the formation of a [CO 3 ] moiety.