Potential Energies and Collision Integrals for Interactions of Carbon and Nitrogen Atoms

Potential energies for C 2 and CN are calculated by a configuration interaction method for those states for which the molecule dissociates into ground state atoms. The potential energy curves are shown graphically; parameters determined from the potential energy wells are tabulated and compared with the corresponding data available from measurements. The potential energies of the 7Σu+ and A' 5 Σ g + states of N 2 are computed from very accurate state-of-the-art molecular structure calculations and improved using the results of spectroscopic measurements, respectively. Transport cross sections are tabulated for a broad range of collision energies. Collision integrals are determined from the cross sections; the C-C and C-N results are tabulated for temperatures in the range 300-30,000 K. The improved collision integrals for N-N interactions differ from the corresponding results of an existing tabulation by a small insignificant amount. The scattering results are used to validate simple methods for estimating collision integrals and to examine the diffusion, viscosity, and thermal diffusion in a gas composed of carbon and nitrogen atoms.

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