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LXCat is an open‐access platform (http://www.lxcat.net) for curating data needed for modeling the electron and ion components of technological plasmas. The data types presently supported on LXCat are scattering cross sections and swarm/transport parameters, ion‐neutral interaction potentials, and optical oscillator strengths. Twenty‐four databases contributed by different groups around the world can be accessed on LXCat. New contributors are welcome; the database contributors retain ownership and are responsible for the contents and maintenance of the individual databases. This article summarizes the present status of the project.

Abstract. In this contribution, the electron swarm parameters of the hydrofluoroolefine HFO1234ze, systematic name 1,3,3,3-Tetrafluoro-1-propene, are experimentally investigated. The analysis of the electron avalanche current measured in a pulsed Townsend experiment yields the effective ionization rate coefficient, the electron drift velocity and the longitudinal electron diffusion coefficient. The subsequent ion current is analyzed as well, to obtain separately the ionization and attachment rate coefficients. Measurements in pure HFO1234ze at different pressures show that the effective ionization rate is strongly influenced by three-body attachment and the three-body attachment rate coefficient is derived.

Gases for electrical insulation are essential for the operation of electric power equipment. This Review gives a brief history of gaseous insulation that involved the emergence of the most potent industrial greenhouse gas known today, namely sulfur hexafluoride. SF paved the way to space-saving equipment for the transmission and distribution of electrical energy. Its ever-rising usage in the electrical grid also played a decisive role in the continuous increase of atmospheric SF abundance over the last decades. This Review broadly covers the environmental concerns related to SF emissions and assesses the latest generation of eco-friendly replacement gases. They offer great potential for reducing greenhouse gas emissions from electrical equipment but at the same time involve technical trade-offs. The rumors of one or the other being superior seem premature, in particular because of the lack of dielectric, environmental, and chemical information for these relatively novel compounds and their dissociation products during operation.

The electrical insulation properties of pure C 4 F 7 N and of C 4 F 7 N/N 2 and C 4 F 7 N/CO 2 mixtures are investigated in a pulsed Townsend setup. The electron rate and transport coefficients and the density-reduced critical electric field of these mixtures are obtained, and a synergy effect is observed in C 4 F 7 N/N 2 and C 4 F 7 N/CO 2 mixtures. The total electron attachment cross section of C 4 F 7 N is estimated based on the attachment rate to C 4 F 7 N in diluted C 4 F 7 N/N 2 , C 4 F 7 N/CO 2 and C 4 F 7 N/O 2 /CO 2 mixtures. Measurements in pure C 4 F 7 N at pressures of a few hundred pascal show that ion kinetics play a major role in C 4 F 7 N discharges and that further modelling is required to assess the electric strength of C 4 F 7 N at high pressures.

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