Linear three-atom molecule CO_2 equilibrium state and interaction analytic potential of the pathway reaction of three-atom system have been successfully constructed by using the two-body perturbation potential. The potential function quantitatively describes the critical characters of CO_2 equilibrium state, and the potential energy surface correctly describes the characters of pathway in O(~1D) + COCX~1Σ~+ )→CO_2→C(~3P) + O_2(X_3Σ_g~- ) reaction. The theoretical analysis is in good agreement with the experimental results.

Key words: CARBON DIOXIDE, POTENTIAL ENERGY SURFACES, OXYGEN