Drift velocity of ions and electrons in non-polar dielectric liquids at high electric field strengths

Ionic and electronic charge carriers are usually injected into dielectric liquids either by ionization by high energy radiation or by photoelectric effect at an electrode. Here, we summarize and discuss data on the drift velocity as a function of applied electric field obtained with these methods. While the drift of ions can be described by Stokes' law of laminar motion up to the highest field strengths measured, the drift of electrons at higher electric field strengths is characterized by an increase of their energy above the thermal energy of the liquid, which enables them to initiate electronic reactions. The importance for the description of electric breakdown processes will be discussed.