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Competition among molecular fragmentation channels described with Siegert channel pseudostates

Edward L. Hamilton·Chris H. Greene
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Abstract

To describe multiple interacting fragmentation continua, we develop a method in which the vibrational channel functions obey outgoing wave Siegert boundary conditions. This paper demonstrates the utility of the Siegert approach, which uses channel energy eigenvalues that possess a negative imaginary part. The electron scattering energy in each such channel is rotated upward, giving it an equal and opposite imaginary part. This permits a natural inclusion of vibrational continua without requiring them to appear as explicit channels in the scattering matrix. Calculations illustrate the application of this theory to photoionization, photodissociation, and dissociative recombination.

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Edward L. Hamilton, Chris H. Greene. 2002-10-23. Competition among molecular fragmentation channels described with Siegert channel pseudostates. https://doi.org/10.1103/physrevlett.89.263003

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