Ion mobility measurements in a 50 cSt viscosity polydimethylsiloxane silicone oil

Using two different time-of-flight techniques (pulse voltage and V.U.V. photons pulse) ion mobility measurements have been performed, at room temperature, on a purified and direct 50 cSt polydimethylsiloxane silicone oil (Rhône Poulenc 604 V 50). These experiments have been carried out in a cell with plane parallel electrodes, for electric fields strengths ranging from 0.4 kV cm
⁻¹
to 8 kV cm
⁻¹
and for three electrode gaps(0.1 cm, 0.15 cm and 0.27 cm). The effect of some additives like N
2
O and C
7
F
14
has also been investigated. The positive ion mobilities (≅ 6.2 10
⁻⁵
cm
²
V
⁻¹
s
⁻¹
) are independent of the additives while, the negative ion mobilities decrease from 6.8 10
⁻⁵
cm
²
V
⁻¹
s
⁻¹
under N
2
to 2.4 10
⁻⁵
cm
²
V
⁻¹
s
⁻¹
in presence of C
7
F
14
.