Kinetic study of the F2 + C2H4 reaction: Disagreement between theory and experiment resolved?

Abstract

Reaction F 2 + C 2 H 4  F + C 2 H 3 F (1) has been studied using a discharge flow reactor combined with an electron impact ionization mass spectrometer. The reaction rate constant was determined either from kinetics of the reaction product, F-atom, formation or from the kinetics of F 2 consumption in excess of C 2 H 4 : k 1 = (7.94 ± 2.06) × 10-12 exp(-(3867 ± 120)/T) cm 3 molecule-1 s-1 at T= 297-833 K. The reaction activation energy, 7.7 ± 0.3 kcal mol-1 , is consistent with current theoretical prediction for the reaction barrier height and seems to solve the long-standing problem of the divergence between theory and experiment.