Plasma Modeling and Prebiotic Chemistry: A Review of the State-of-the-Art and Perspectives

Abstract

We review the recent progress in the modeling of plasmas or ionized gases, with compositions compatible with that of primordial atmospheres. The plasma kinetics involves elementary processes by which free electrons ultimately activate weakly reactive molecules, such as carbon dioxide or methane, thereby potentially starting prebiotic reaction chains. These processes include electron–molecule reactions and energy exchanges between molecules. They are basic processes, for example, in the famous Miller-Urey experiment, and become relevant in any prebiotic scenario where the primordial atmosphere is significantly ionized by electrical activity, photoionization or meteor phenomena. The kinetics of plasma displays remarkable complexity due to the non-equilibrium features of the energy distributions involved. In particular, we argue that two concepts developed by the plasma modeling community, the electron velocity distribution function and the vibrational distribution function, may unlock much new information and provide insight into prebiotic processes initiated by electron–molecule collisions.

The spark of life: discharge physics as a key aspect of the Miller–Urey experiment

“…The next question is whether it is possible to describe the primary events, and at least the onset of the chemical kinetics, in the complex mixture used by Miller. Indications in this sense have been reported in a recent work [24] where it has been shown that the electron energy spectrum can be determined using state-ofthe-art methods for a realistic mixture matching that of the Miller-Urey original experiment and for variants describing less reducing primordial atmospheres. A model including many of the sophistications described above has been developed for lightning in the primordial atmosphere [25].…”

Particle Propagation and Electron Transport in Gases

“…Furthermore, the method has been recently coupled with detailed plasma chemistry models in Refs. [71][72][73][74].…”

Benchmark calculations for anisotropic scattering in kinetic models for low temperature plasma

“…code is an MC code for the simulation of electrons under swarm conditions. Recent work with ELIOS includes benchmarking against solutions of two-term and multi-term BE solvers and simulations in atomic and molecular gases using variance reduction techniques [31,32,43].…”