Three-block model of the kinetics of vibrationally excited I2(X) molecules in the active media of oxygen — iodine lasers

A three-block model of the kinetics of vibrationally excited I₂(X) molecules in the active media of chemical oxygen — iodine lasers is developed. Instead of the system of equations describing a change in the concentrations of I₂(X, u) (u = 0 — 47) molecules, this model uses equations for the total concentrations of iodine molecules belonging to the blocks of vibrational levels with u ≤ 10, u = 11 — 24, and u ≥ 25. Effective deactivation rate constants of I₂(X, 11 ≤ u ≤ 24) molecules are found for laser media of different compositions. The results of calculations performed using the proposed model agree with experimental data and are close to the parameters calculated previously by using the total system of equations for populations of individual vibrational levels of I₂(X, u).