Vibrational Excitation of N2(B, C) and N+2(B) States in N2 and N2-H2 Flowing Microwave Discharges

The ro-vibrational spectra of N2 microwave discharges have been analysed by emission spectroscopy. It is deduced the rotational and vibrational temperatures of N2 states. The characteristic of vibrational temperature T1 of the N2 (X, v) ground state has been specifically determined.It has been found that the N2 (C, B, v') and N+2 (B, v') radiative states are directly excited by electron collisions on the N2 (X,v) ground state at a N2 gas pressure of 0.1 Torr (discharge tube of 5 mm I.D, microwave power 100 Watt) with a T1 value near 104 K. At higher gas pressure up to 5 Torr, the N2 (C, v') states remain alone to be mainly excited by electron collisions on N2 (X, v). It is considered the excitations of the N2 (B, v') states by collisions of electrons and N2 (X,v > 4) vibrational molecules on the N2 (A) metastable states.With x < 9% H2 into N2, it is observed an increase of N2, 2nd pos intensity, resulting of an increase of high energy electrons. Inversely, the N2, 1st pos intensity decreased, partly following the decrease of low energy electrons (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)