Toward reaction mechanisms for plasma chemistry: CO₂ neutral kinetics as a test case and new directions using ChemCat

Non-equilibrium effects are ubiquitous in laboratory plasmas and need to be considered to optimize the reactor performance for specific applications. Their impact on plasma chemistry is particularly noteworthy with the origin of discrepancies between experiments and modelling difficult to pinpoint. The overarching of recent efforts in the low temperature plasma community, including the ChemCat project, is to develop reaction mechanisms, a class of electron and neutral kinetics datasets which, although, (often) incomplete, allow to provide accurate species densities prediction for a large range of conditions. One of the main challenges is the accessibility and documentation of high-quality data [1]. The LXCat team, in collaboration with the LTP community is developing a new infrastructure, ChemCat, for storing data and running online calculations. As a test case, we present a reduced chemistry dataset for modelling neutral species kinetics in warm CO₂ plasma discharges. Code to code testing is first done and benchmark calculations are presented again theoretical results (i.e. thermodynamics) and shock-tube experiments. The final dataset is used to showcase the capabilities of the new ChemCat platform [2] and how it can help toward more reliable (and faster) calculations.

[1] Carbone, E. et al. (2021). Atoms, 9 (1), 16, 10.3390/atoms9010016

[2] https://github.com/LXCat-project