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arXiv · 0901.0672

Geometrical phase driven predissociation: Lifetimes of 2^2 A' levels of H_3

Juan Blandon·Viatcheslav Kokoouline
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Abstract

We discuss the role of the geometrical phase in predissociation dynamics of vibrational states near a conical intersection of two electronic potential surfaces of a D_{3h} molecule. For quantitative description of the predissociation driven by the coupling near a conical intersection, we developed a method for calculating lifetimes and positions of vibrational predissociated states (Feshbach resonances) for X_3 molecule. The method takes into account the two coupled three-body potential energy surfaces, which are degenerate at the intersection. As an example, we apply the method to obtain lifetimes and positions of resonances of predissociated vibrational levels of the 2^2 A' electronic state of the H_3 molecule. The three-body recombination rate coefficient for the H+H+H -> H_2+H process is estimated.

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Juan Blandon, Viatcheslav Kokoouline. 2009-01-06. Geometrical phase driven predissociation: Lifetimes of 2^2 A' levels of H_3. https://doi.org/10.1103/physrevlett.102.143002

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