The Mobility of Negative Ions in $\hbox{CF}_{3} \hbox{I}$, $\hbox{CF}_{3}\hbox{I}{-}\hbox{N}_{2}$ , $\hbox{CF}_{3}\hbox{I}{-}\hbox{Ar}$, $\hbox{CF}_{3}\hbox{I}{-}\hbox{Xe}$, $\hbox{C}_{2}\hbox{F}_{6}$, and $\hbox{CHF}_{3}$, and of Positive Ions in $\hbox{C}_{2} \hbox{F}_{4}$ and $\hbox{c-C}_{4}\hbox{F}_{8}$

Using a pulsed Townsend technique, the drift velocity and the mobility of positive ions in C
₂
F
₄
and C
₄
F
₈
and those of negative ions in C
₂
F
₆
, CHF
₃
, and CF
₃
I and its mixtures with N
₂
, Ar, and Xe are reported. The overall range of the density-normalized electric field is 4-600 times10
<sup>-17

-

V</sup>
ldrcm
²
. 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 C
₂
F
₄

⁺
for C
₂
F
₄
and c-C
₄
F
₈
, F
^-
for C
₂
F
₆
and CHF
₃
, and I
^-
for CF
₃
I. The use of more comprehensive theories of ion motion considering the influence of a permanent dipole moment (CHF
₃
and CF
₃
I) has provided reasonable agreement between low-field measured and calculated mobilities. The mobility of negative ions in CF
₃
I-N
₂
, CF
₃
I-Ar, and CF
₃
I-Xe mixtures agrees reasonably well with the predicted values by Blanc's law.