Plasmas Afterglows with N2 for Surface Treatments New Results

It presently reported new results of previous books Plasmas Afterglows with N2 for Surface Treatments, editions 1-3, published by Bookpi – editions in 2021, 2022 and 2023.

These previous books were focused on the production of plasma active species with \(\mathrm{N}_2\) which contain molecules in electronic, vibrational and rotational states and dissociated atoms or radicals.

The method of NO titration of \(\mathrm{N}\) and \(\mathrm{O}\)-atoms density and that of the percentage of afterglow resulting from \(\mathrm{N}\)-atom recombination were detailed. The relevant kinetics equations in the afterglow and the intensity ratio method to obtain the radiative species density from that of \(\mathrm{N}\)-atoms were elucidated. By this method, it was obtained the densities of \(\mathrm{O}, \mathrm{H}\) and \(\mathrm{C}\)-atoms, of \(\mathrm{N}_2(A)\) and \(\mathrm{N}_2(X, v>13)\) metastable molecules, and of \(\mathrm{NH}, \mathrm{NO}\) and \(\mathrm{CN}\) radicals. The plasmas and afterglows were obtained by a microwave supply at reduced gas pressures in the Montreal and Toulouse Univ. and at atmospheric gas pressure in the Orsay, Pau and Toulouse Univ.

From recent results obtained in Laplace Lab. concerning the Laser fluorescence measurements (TALIF) of \(\mathrm{N}\) and \(\mathrm{H}\) atoms density in \(\mathrm{N}_2-\mathrm{H}_2\) afterglows (PHD thesis of V.Ferrer, Toulouse 2023), it is deduced in the first chapter that the rate coefficient of the \(\mathrm{N}+\mathrm{H}+\mathrm{M}\left(\mathrm{N}_2, \mathrm{Ar}\right) \rightarrow \mathrm{NH}+\mathrm{M}\left(\mathrm{N}_2, \mathrm{Ar}\right)\) reaction, chosen in Chapter 2, 4 and 13 of the previous books (editions 1-3, 2021-23) must be divided by 50 with \(M=\mathrm{N}_2\) and 20 with \(M=A r\) that confirms the assumed value of \(10^{-33} \mathrm{~cm}^6 \mathrm{~S}^{-1}\) for \(M=\mathrm{N}_2\) of Gordiets et al. 1998.

It is also discussed in this new chapter on the method to obtain the a \({ }_{N+N}\) part of the \(N+N\) recombination to produce the \(N_2\left(B, v^{\prime}=11\right)\) radiative state, the key to calibrating the \(\mathrm{N}\)-atom density in the flowing afterglow.