MODELING OF PLASMA-CHEMICAL REACTIONS IN GAS-MIXTURE OF CO2-LASERS .1. GAS DECOMPOSITION IN PURE CO2 GLOW-DISCHARGE

The chemistry of a pure CO2 glow discharge is modelled as a first step in description of CO2 lasers plasma-chemical reactions. The equilibri um conversion of CO2 into CO strongly depends on E/N ratio. It grows f rom few percent for E/N =2 x 10(-16) V cm2 to more then 70% for E/N ap proximately 9 x 10(-16) V cm2. The X(e) values are only slightly influ enced by the change of electron density and temperature. The role of i ons and of the CO(a3PI) excited electronic state in recombination of C O as well as of heterogeneous recombination is studied. The time requi red to reach the steady-state concentrations of chemical species in th e system varies from few seconds for high E/N values up to hours in th e other end of investigated region; it increases with the fall of disc harge current and with the fall of E/N. Satisfactory agreement with ex perimental data is achieved.