Water radical cations,the crucial intermediates in many aqueous reactions and biochemical processes,are difficult to investigate experimentally due to their short lifetime andlowabundance.Herein,ahomemade device based...Water radical cations,the crucial intermediates in many aqueous reactions and biochemical processes,are difficult to investigate experimentally due to their short lifetime andlowabundance.Herein,ahomemade device based on energy-tunable discharge was employed to deposit suitable amounts of energy to atmospheric pressure pure water vapor for abundant production of water radical cations,stabilized as(H_(2)O)n^(+·)(n=2-5)with a maximal abundance of≥8.3×10^(6) cps for(H_(2)O)_(2)^(+·),characterized by mass spectrometry(MS).The abundance of water radical cations was optimized by adjusting the experimental parameters such as the discharge voltage(2.5 kV),temperature of the MS inlet(140℃),carrier gas flow(20mL/min),and the distance between the discharge tip and MS inlet(12 mm).The ambient formation of water radical cationswas further confirmedby thehigh reactivity of as-prepared water radical cations,which reacted with benzene,ethyl acetate,and dimethyl disulfide instantly,showing rich chemistry with ionic and radical characteristics.Moreover,the computations usingCCSD(T)//MP2 method and density functional theory confirmed that the O-O single-electron bound dimer(B),as well as the hydronium hydroxyl radical complex(A),accounted for the unusual chemistry of the water radical cations,providing a facile approach to access the high reactivity ofwater radical cations under the ambient conditions.展开更多
基金supported by a grant from the National Natural Science Foundation of China(grant no.215201-02007)the US National Science Foundation(grant no.1905087).
文摘Water radical cations,the crucial intermediates in many aqueous reactions and biochemical processes,are difficult to investigate experimentally due to their short lifetime andlowabundance.Herein,ahomemade device based on energy-tunable discharge was employed to deposit suitable amounts of energy to atmospheric pressure pure water vapor for abundant production of water radical cations,stabilized as(H_(2)O)n^(+·)(n=2-5)with a maximal abundance of≥8.3×10^(6) cps for(H_(2)O)_(2)^(+·),characterized by mass spectrometry(MS).The abundance of water radical cations was optimized by adjusting the experimental parameters such as the discharge voltage(2.5 kV),temperature of the MS inlet(140℃),carrier gas flow(20mL/min),and the distance between the discharge tip and MS inlet(12 mm).The ambient formation of water radical cationswas further confirmedby thehigh reactivity of as-prepared water radical cations,which reacted with benzene,ethyl acetate,and dimethyl disulfide instantly,showing rich chemistry with ionic and radical characteristics.Moreover,the computations usingCCSD(T)//MP2 method and density functional theory confirmed that the O-O single-electron bound dimer(B),as well as the hydronium hydroxyl radical complex(A),accounted for the unusual chemistry of the water radical cations,providing a facile approach to access the high reactivity ofwater radical cations under the ambient conditions.