The dependence of electron capture and ionization processes on the pre-collision electronic distribution is examined for the systems primarily in the energy range 1 - 15 keV. Populations of the capture and ionization channels as well as the coherence of the post-collision electronic distribution of the capture product are formulated using the classical trajectory Monte Carlo (CTMC) method. Total capture and ionization cross sections arising from initially aligned Na(3p) targets exhibit transient behaviour near the velocity-matching energy of 5.7 keV. This observation is described in terms of anisotropy parameters; anisotropy effects are also analysed for the capture states n = 2, 3 and 4. In addition to the population manifold, we present theoretical calculations of the alignment parameter and the z-component of the dipole moment , in order to relate the alignment of the post-collision charge cloud to that of the initial Na(3s, , ) target states. The z-component of the cross product of the angular momentum and the Runge - Lenz vector is used to describe the orientation of the post-collision product generated from the aligned Na(, ) pre-collision reactants.

The classical trajectory Monte Carlo method is used to calculate coherence parameters for electron capture to H(n=2, 3 and 4) in 30 to 250 keV H++He collisions. The parameters evaluated are the x- and z-components of the dipole moment (D) and the z-component of the perihelion velocity of the captured election (L*A). The calculated integral values are found to be in reasonable agreement with available experimental results. Components of the dipole moment and (L*A) were also evaluated as a function of projectile scattering angle. Here, rapid variations of the parameters are observed near the Thomas angle that indicate the transition from the hard, large angle collisions between the projectile and target nucleus to the soft, small angle scattering between the projectile and active electron.

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