Rotational Excitation Of H2 Research Articles

Rotational excitation of H2 and N2 molecules by electron impact

The rotational excitation of the H2 and N2 molecules from (J→J+2,J=0) and (J→J+2,J=1) states by electron impact is studied, in the framework of the regional-plane-wave approximation. The empirical cut-off parameterρ, involved in these calculations, is varied to give the best fit to the experimental data of Srivastava and co-workers.

Multiple-scattering approach to the vibrational-rotational excitation of molecules by slow electrons

The cross sections for vibrational and rotational excitation of H2, Li2, Na2 and K2 by slow electrons are calculated in the adiabatic approximation using a zero range potential model to obtain the amplitude of electron scattering for a 'frozen' molecule. The advantage of the zero range potential model is the possibility of taking into account explicitly the effect of multiple scattering. The results are compared with the available experimental data and other calculations.

Rotational excitation of H2 in collision with He

Converged close coupling cross sections for the vibrationally and rotationally inelastic processes for the system H2+He are reported. (AIP)

Spin-lattice relaxation and the anisotropic part of the H2–He and H2–Ne intermolecular potential

The spin-lattice relaxation time of H2 infinitely dilute in He and Ne gases has been measured from 20–140 °K. Scattering cross sections for molecular reorientation and rotational excitation of H2 in collision with He and Ne have been computed. By comparison between experiment and calculation, using theoretical relationships between cross sections and measured relaxation rates, parameters are obtained for the anisotropic part of the H2–He and H2–Ne potential surfaces.

The rotational excitation of molecular hydrogen

Close-coupling calculations are carried out of the 0-2 rotational excitation of H2 by the impact of H, He and H2 and of the 0-2 rotational excitation of D2 by H impact. The failure of the distorted-wave approximation at high impact energies is demonstrated. The close-coupling result for He impact at 0 15 eV differs by less than 10% from the result of a semi-classical calculation. Excitation cross sections and angular distributions and elastic cross sections are calculated. For H-H2 and H2-H2, rate coefficients are also given.