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Nuclear and High Energy Physics

Low energy electron scattering from polyatomic targets

Profile image of Helen SilvaHelen Silva

2009, Journal of Physics: Conference Series

https://doi.org/10.1088/1742-6596/194/1/012027
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Abstract

Until recently the principal barrier to the accurate theoretical description of electronic collisions with polyatomic molecules was the problem of scattering by a nonlocal potential which is arbitrarily asymmetric. The last five or six years have seen the development of numerical techniques capable of solving the potential scattering problem, and the first applications of methods for treating many-body aspects of collisions of electrons with polyatomic molecules are beginning to appear in the literature. We describe the complex Kohn method and the use, in scattering calculations, of methods for treating electronic correlation which are standard in bound-state quantum chemistry. As examples of the application of these ideas we present the results of calculations on electron scattering from CH4, SiH4 and C 2 H6. All of these molecules exhibit Ramsauer-Townsend minima at low impact energies which are entirely correlation effects.

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