A kinetic study of the reaction of copper atoms in the gas phase with molecular oxygen at 300 K in microwave-induced plasma afterglows

Abstract

The reaction between gas-phase copper atoms Cu_g(4²S) and molecular oxygen has been investigated in a fast-flow reactor in the pressure range 5.5–12 Torr. As a source of Cu_g the new technique of plasma afterglow atomization of CuCl and Cu(CH₃CO₂)₂ in H₂/Ar microwave induced plasmas was used. The copper atoms were detected by atomic absorption spectroscopy. The rate constant for the reaction Cu_g+O₂+Ar → CuO₂+Ar was found to be (3.8±0.2)× 10^–31 cm⁶ molecule^–2s^–1 at 300 K. For the diffusion coefficient of Cu_g in argon the value of D_Cu,Ar= 219.9±9.2 cm² Torr s^–1 was derived at 300 K.