Cross-section and rate coefficient calculation for electron impact excitation, ionisation and dissociation of H2 and OH molecules

Abstract

The weighted total cross-section (WTCS) theory is used to calculate electron impact excitation, ionisation and dissociation cross-sections and rate coefficients of OH, H2, OH+, H2 +, OH- and H2 - diatomic molecules in the temperature range 1500–15000 K. Calculations are performed for H2(X, B, C), OH(X, A, B), H2 +(X), OH+(X, a, A, b, c), H2 -(X) and OH-(X) electronic states for which Dunham coefficients are available. Rate coefficients are calculated from WTCS assuming Maxwellian energy distribution functions for electrons and heavy particles. One and two temperature (θe and θg respectively for electron and heavy particles kinetic temperatures) results are presented and fitting parameters (a, b and c) are given for each reaction rate coefficient: k(θ) = a (θb)exp (-c/θ).