Experimental and Theoretical Study of Reactions between Manganese Oxide Cluster Cations and Hydrogen Sulfide (cited: 2)

Manganese oxide cluster cations Mn_m¹⁸O_n⁺ were prepared by laser ablation and reacted with hydrogen sulfide (H₂S) in a fast flow reactor under thermal collision conditions. A time-of-flight mass spectrometer was used to detect the cluster distributions before and after the interactions with H₂S. The experiments suggest that oxygen-for-sulfur (O/S) ex-change reaction to release water took place in the reactor for most of the manganese oxide cluster cations: Mn_m¹⁸O_n⁺+H₂S→Mn_m¹⁸O_n-1S⁺+H₂¹⁸O. Density functional theory cal-culations were performed for reaction mechanisms of Mn₂O₂⁺, Mn₂O₃⁺, and Mn₂O₄⁺. The computational results indicate these O/S exchange reactions are both thermodynamically and kinetically favorable, thus in good agreement with the experimental observations. The O/S exchange reactions identified in this gas-phase cluster study parallel similar behavior of related condensed phase reaction systems.