Mobility of Electrons in Dielectric Liquids
TL;DR: In this paper, the drift velocities of electrons in eight saturated hydrocarbons and in tetramethylsilane were determined from the rise time in the conductivity found with a fast response circuit when a parallel-plate cell was subjected to a pulse of 2.MeV x rays.
Abstract: The drift mobilities of electrons in eight saturated hydrocarbons and in tetramethylsilane were determined from the rise time in the conductivity found with a fast‐response circuit when a parallel‐plate cell was subjected to a pulse of 2‐MeV x rays. Careful purification was required to avoid capture of the electrons by impurity centers. The measured mobilities ranged from 0.09 cm2 V−1·sec−1 in n‐hexane to 90 in tetramethylsilane. Drift velocities were linear with the applied field up to velocities above 106 cm/sec. Temperature coefficients of the mobility were found to be positive in n‐hexane and neohexane. Speculations are offered about the nature of the processes which determine the mobilities.
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TL;DR: In this paper, a comprehensive account of streamer propagation in dielectric fluids in point-plane geometries is presented, and the relation between shock wave and streamer velocities is investigated.
Abstract: In this paper we present a comprehensive account of our results on streamer propagation in dielectric fluids in point‐plane geometries. Propagation velocities for both positive and negative streamers have been determined as a function of the following parameters: temperature, pressure, density, viscosity, composition, and conductivity. Effects of voltage and interelectrode spacing were examined. Current and light emission during streamer growth were measured. The relation between shock wave and streamer velocities was investigated. Small concentrations of low‐ionization potential additives markedly accelerated the positive streamers, while electron scavengers accelerated the negative streamers. Mechanisms to account for these observations are discussed.
372 citations
TL;DR: In this paper, the physical properties of electronic charge carriers (electrons, holes) in non-polar and polar liquids are discussed and the results are used to explain or discuss certain electric conduction phenomena which occur when these liquids are subjected to a high electric field strength.
Abstract: A review is given on the physical properties of electronic charge carriers (electrons, holes) in non-polar and polar liquids. The results are used to explain or discuss certain electric conduction phenomena, which occur when these liquids are subjected to a high electric field strength. Electronic conduction in ultrapure liquids is finding an increasing number of applications.
169 citations
CERN1
TL;DR: In the field of particle physics, a large amount of the present knowledge about elementary particles has been established through a continuing refinement of techniques for measuring the trajectories of individual charged particles.
Abstract: Much of our present knowledge about elementary particles has been established through a continuing refinement of techniques for measuring the trajectories of individual charged particles. Only in recent years has a different class of detectors—calorimeters—been widely employed, but these have already greatly influenced the scope of experiments.
155 citations
TL;DR: In this article, stable electronic charge carriers have been observed in n−hexane, n−pentane, benzene, and methylbutene with room temperature mobilities of 0.07, 0.6, and 3.6 cm2 V−1·sec−1, respectively.
Abstract: Stable electronic charge carriers have been observed in n‐hexane, n‐pentane, benzene, and methylbutene with room temperature mobilities of 0.07, 0.07, 0.6, and 3.6 cm2 V−1·sec−1, respectively. The charge carriers were injected into the highly purified hydrocarbon liquids by photoemission of electrons from a low work function surface. Mobilities increase rapidly with temperature and obey an Arhennius expression with activation energies of 4.3 kcal mole−1 in hexane and 2.6 kcal mole−1 in methylbutene. The carriers in hexane could be drawn out of the liquid into the vapor and had a higher mobility in the solid than in the liquid at temperatures near the melting point. Current versus voltage measurements indicate that the injection process is controlled by transmission over the image barrier at the cathode. The mobilities of the injected charges in these fluids are more than 100 times ionic mobilities in the same fluids but considerably less than the mobilities of electrons in the rare‐gas liquids. The free e...
124 citations
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TL;DR: In this article, the data of E. J. Ryder on the mobility of electrons in electric fields up to 40,000 volts per cm are analyzed and it is estimated that electron “temperatures as high as 4000°K have been produced in specimens having temperatures of atomic vibration of 300° K.
Abstract: The data of E. J. Ryder on the mobility of electrons in electric fields up to 40,000 volts per cm are analyzed. The mobility decreases many fold due to the influence of scattering by optical modes and due to increases of electron energy. It is estimated that electron “temperatures” as high as 4000°K have been produced in specimens having temperatures of atomic vibration of 300° K. The critical drift velocity above which there are deviations from Ohm's law is about 2.6 × 106 cm/sec. This is three times higher than the elementary theory and on explanation in terms of complex energy surfaces is proposed.
416 citations
TL;DR: In this paper, the Hartree field of an atom is assumed not to change on passing from gas to liquid, and the screening of the long-range polarization potential is given by a self-consistent local field, which is found in terms of the pair correlation function.
Abstract: The scattering of electrons moving through nonpolar liquids is discussed. The Hartree field of an atom is assumed not to change on passing from gas to liquid. The screening of the long-range polarization potential is given by a self-consistent local field, which is found in terms of the pair correlation function. A microscopic dielectric function follows as a byproduct. The overlap of atomic force fields in the liquid is handled by the use of an effective potential suggested by Cohen. Detailed calculations are made for electrons in liquid argon. The principal result is that the Ramsauer minimum no longer exists in the liquid. The drift velocity in a steady electric field is found from the solution of the Boltzmann equation given by Cohen and Lekner. Agreement between experiment and theory is good.
255 citations
245 citations