LAUSR

The electrical insulation properties of pure C4F7N and of C4F7N/N2 and C4F7N/CO2 mixtures are investigated in a pulsed Townsend setup. The electron rate and transport coefficients and the density-reduced critical electric field of these mixtures are obtained, and a synergy effect is observed in C4F7N/N2 and C4F7N/CO2 mixtures. The total electron attachment cross section of C4F7N is estimated based on the attachment rate to C4F7N in diluted C4F7N/N2, C4F7N/CO2 and C4F7N/O2/CO2 mixtures. Measurements in pure C4F7N at pressures of a few hundred pascal show that ion kinetics play a major role in C4F7N discharges and that further modelling is required to assess the electric strength of C4F7N at high pressures.