Thermal decomposition of CF3I using I-atom absorption

I-atom atomic resonance absorption spectrometry (ARAS) has been developed and applied to measure the thermal decomposition rate constant for CF3I (+M) → CF3 + I (+M). The I-atom curve-of-growth (λ = 183 nm) was determined using this reaction, and, for [I] ⩽3 × 1012 molecules cm−3, (ABS) = 1.9215 × 10−13 [I], yielding σ = 1.933 × 10−14 cm2. Measured rate constants can be expressed by k1 = 3.24 × 10−9 exp(−17286 K/T) cm3 molecule−1 s−1 (±56%, 1033 ⩽ T ⩽ 1285 K). RRKM theory has been applied to rationalize this result.