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arXiv · 1406.3825

Signatures of classical bifurcations in the quantum scattering resonances of dissociating molecules

Pierre Gaspard
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Abstract

A study is reported of the quantum scattering resonances of dissociating molecules using a semiclassical approach based on periodic-orbit theory. The dynamics takes place on a potential energy surface with an energy barrier separating two channels of dissociation. Above the barrier, the unstable symmetric-stretch periodic orbit may undergo a supercritical pitchfork bifurcation, leading to a classically chaotic regime. Signatures of the bifurcation appear in the spectrum of resonances, which have a shorter lifetime than classically expected. A method is proposed to evaluate semiclassically the energy and lifetime of the quantum resonances in this intermediate regime.

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Pierre Gaspard. 2014-06-15. Signatures of classical bifurcations in the quantum scattering resonances of dissociating molecules. https://doi.org/10.1007/s00214-014-1519-0

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