Eley-Rideal and Langmuir-Hinshelwood Recombination Coefficients for Oxygen on Silica Surfaces

A Finite-Rate Gas-Surface Interaction Model Informed by Fundamental Computational Chemistry Simulations

“…This now led to a certain rate of recombination reactions, which of course depended upon where the adsorbed oxygen was placed. By following this invalid modeling approach, remarkable agreement with measurements from air plasma experiments was reported [15,16]. In contrast, our computational chemistry simulations predict that such cleaved surfaces reconstruct into the lower-energy, stable surface configurations seen in Fig.…”

“…A substantial amount of previous research had been conducted in this area by two European research groups [15][16] and [17][18][19][20][21]. In fact, one group recently published an article (in 2011) where a finite-rate catalytic model is developed for air-silica interactions using computational chemistry simulations [21].…”

“…These prior studies [15][16][17][18][19][20][21] have been published in high quality computational chemistry and surface science journals. The above critical review clearly demonstrates the lack of rigorous collaboration and understanding between computational chemistry researchers and aerothermodynamics researchers.…”

Molecular Physics of Elementary Processes Relevant to Hypersonics: Atom-Molecule, Molecule-Molecule and Atoms-Surface Processes

“…Although some experiments have been carried out to measure such coefficients [6], some of the related publications quote the only effective catalytic efficiency values ( γ eff ,i = ′ γ i = γ i ⋅ β i ) and only a few of them quote β i coefficients that in CFD simulations are frequently assumed to be 1 (i.e., fully energy accommodation assumption). On the contrary, theoretical investigations developed at molecular dynamics level [60] have shown that only a fraction of the total exothermicity delivered in the Eley-Rideal (E-R) recombination processes of O and N on silica surfaces is transferred to the substrate as heat flux and that the main part of that energy is disposed into rotation, vibration or translation motions of the newly formed molecules. Therefore, the energy accommodation coefficient β i associated with the recombination reaction can hardly be taken as a unit.…”

A Gas-Surface Interaction Model based on Accelerated Reactive Molecular Dynamics for Hypersonic Conditions including Thermal Conduction

“…A substantial amount of previous research had been conducted in this area by two European research groups; one located in Bari, Italy [15][16] and the other in Barcelona, Spain [17][18][19][20][21]. In fact, the group from Spain recently published an article (in 2011) where a finite-rate catalytic model is developed for airsilica interactions using computational chemistry simulations [21].…”