The thermal decomposition of TiCl{sub}4 was studied behind reflected shock waves at temperatures 1300 K≤T≤1500 K at pressures between 1.3 and 3.7 bar. Atomic resonance absorption spectroscopy (ARAS) was applied for time-resolved measurements of Cl atoms in gas mixtures containing 0.2-45 ppm TiCl{sub}4 highly diluted in argon. The signals obtained were kinetically evaluated by computer simulation based on a simplified reaction mechanism. The very sensitive Cl-ARAS technique allowed us to choose reaction conditions under which the Cl profiles were almost only dependent on the rate coefficients k{sub}1 and k{sub}2 of the following reactions: TiCl{sub}4+M←→ TiCl{sub}3+Cl+M TiCl{sub}3+M←→ TiCl{sub}+Cl+M K{sub}1=10{sup}(18.73±0.35)exp(-40,370±1120 K/T) cm{sup}3 mol{sup}-1 s{sup}-1 K{sub}2=10{sup}(18.05±0.28)exp(-46,500±1260 K/T) cm{sup}3 mol{sup}-1 s{sup}-1 Within our experimental uncertainty, we found no falloff effects.
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