Kinetics of the thermal decomposition of CH2F2

Highlights: • Shock tube experiments on the thermal decomposition of CH₂F₂. • Kinetic analysis of the HF formation profiles. • Theory corroborates and extrapolates the experimental rate constants. Kinetics of the thermal decomposition reaction CH₂F₂ → CHF + HF was studied by laser absorption measurements in a shock tube. The rate constants were determined by analyzing temporal profiles of HF produced in pyrolysis of CH₂F₂ over the temperature range 1577–2214 K at pressure of ∼100 kPa in Ar bath. The results were well reproduced by master equation analysis based on RRKM theory and classical trajectory calculations, which gave the following rate constant expressions: k_∞ = 2.34 × 10¹⁵ exp(−41,550 K/T) s⁻¹, k₀ = 5.33 × 10²⁵ (T/K)^−8.635 exp(−44,190 K/T) cm³ molecule⁻¹ s⁻¹, and F_cent = 0.13.