Molecular Physics of Elementary Processes Relevant to Hypersonics:Electron-Molecule Collisions

摘要

Non-resonant, electron-impact, vibro-electronic excitation cross sections, involving vibrationally excited N2molecules, to the mixed valence-Rydberg b,c,o 1Πu and b′,c′,e′ 1?u+ singlet states are presented. These cross sectionsare calculated using the so-called similarity approach, accounting for the vibronic coupling among excited states, andcompared with the experiments and different theoretical calculations.New cross sections for the electron-impact resonant vibrational excitation of CO2 molecule are calculated, for thesymmetric stretching mode, as a function of the incident electron energy and for the transitions (υi , 0,0)→(νf , 0,0) withνi= 0,1,2 and for some selected value of νf in the interval νi ≤νf ≤10. A resonance potential curve and associatedwidths are calculated using the R-matrix method. Rate coefficients, calculated by assuming a Maxwellian electron energydistribution function, are also presented for the same (νi , 0,0)→(νf , 0,0) transitions.Electron-impact cross sections and rate coefficients for resonant vibrational excitations involving the diatomic species N2,NO, CO, O2 and H2, for multi-quantic and mono-quantic transitions, are reviewed along with the cross sections and ratesfor the process of the dissociative electron attachment to H2 molecule, involving a Rydberg excited resonant state of the H2- ion.