Experimental and theoretical studies of reactions of neutral vanadium and tantalum oxide clusters with NO and NH3

Reactions of neutral vanadium and tantalum oxide clusters with NO, NH3, and an NO/NH3 mixture in a fast flow reactor are investigated by time of flight mass spectrometry and density functional theory (DFT) calculations. Single photon ionization through a 46.9 nm (26.5 eV) extreme ultraviolet (EUV) laser is employed to detect both neutral cluster distributions and reaction products. Association products VO3NO and V2O5NO are detected for VmOn clusters reacting with pure NO, and reaction products, TaO3,4(NO)1,2, Ta2O5NO, Ta2O6(NO)1–3, and Ta3O8(NO)1,2 are generated for TamOn clusters reacting with NO. In both instances, oxygen-rich clusters are the active metal oxide species for the reaction MmOn+NO→MmOn(NO)x. Both VmOn and TamOn cluster systems are very active with NH3. The main products of the reactions with NH3 result from the adsorption of one or two NH3 molecules on the respective clusters. A gas mixture of NO:NH3 (9:1) is also added into the fast flow reactor: the VmOn cluster system forms stable, obse...