Collision-induced dissociation of [UO (NO ) ] and [UO (NO ) (O )] and reactions of product ions with H O and O.

Electrospray ionization (ESI) can produce a wide range of gas-phase uranyl (UO ) complexes for tandem mass spectrometry studies of intrinsic structure and reactivity. We describe here the formation and collision-induced dissociation (CID) of [UO (NO ) ] and [UO (NO ) (O )] . Multiple-stage CID experiments reveal that the complexes dissociate in reactions that involve elimination of O , NO , or NO , and subsequent reactions of interesting uranyl-oxo product ions with (neutral) H O and/or O were investigated. Density functional theory (DFT) calculations reproduce experimental results and show that dissociation of nitrate ligands, with ejection of neutral NO , is favored for both [UO (NO ) ] and [UO (NO ) (O )] . DFT calculations also suggest that H O adducts to products such as [UO (O)(NO )] spontaneously rearrange to create dihydroxides and that addition of O is favored over addition of H O to formally U(V) species.