Variation of the electron attachment to n-C4F1 with temperature

Publisher Website
Google Scholar
Abstract
The total electron attachment rate constant ka(〈ε〉) for n‐C4F10 has been measured using an electron swarm technique in the mean electron energy, 〈ε〉, range 0.76 to 4.81 eV and over the temperature, T, range 300 to 750 K. The measured ka(〈ε〉,T) and the total electron attachment cross section σa(ε,T) determined from these by unfolding are reported. The ka(〈ε〉) first decrease slowly with T between 300 and 400 K, then decrease precipitously between 400 and ∼500 K, and subsequently increase for T>500 K. The overall variation of ka with T depends on 〈ε〉. From the measured dependence of ka(〈ε〉) on the total gas number density and T we determined the contribution of dissociative and nondissociative attachment to ka as a function of 〈ε〉; the contribution of nondissociative attachment decreases with T and the contribution of dissociative attachment increases with T. The ratio Rd/t of the dissociative to the total electron attachment is small at low 〈ε〉 and T, but it increases with both 〈ε〉 and T and reaches unity for T>500 K and 〈ε〉>1.7 eV. These results are discussed in relation to similar earlier work on C2F6 and C3F8.