The Mobility of Negative Ions in CF₃ I, CF₃I-N₂ , CF₃I-Ar, CF₃I-Xe, C₂F₆, and CHF₃, and of Positive Ions in C₂ F₄ and c-C₄F₈

Using a pulsed Townsend technique, the drift velocity and the mobility of positive ions in C2F4and C4F8and those of negative ions in C2F6, CHF3, and CF3I and its mixtures with N2, Ar, and Xe are reported. The overall range of the density-normalized electric field is 4-600 times10-17-Vldrcm2. Ion identification is provided by means of previous studies on partial ionization and electron attachment. Thus, it is suggested that the predominant drifting ion in the discharge is C2F4+for C2F4and c-C4F8, F-for C2F6and CHF3, and I-for CF3I. The use of more comprehensive theories of ion motion considering the influence of a permanent dipole moment (CHF3and CF3I) has provided reasonable agreement between low-field measured and calculated mobilities. The mobility of negative ions in CF3I-N2, CF3I-Ar, and CF3I-Xe mixtures agrees reasonably well with the predicted values by Blanc's law.