Photodetachment of H− ion near two repulsive centers

Based on a theoretical model for the photodetachment of negative ion near a repulsive center, we study the photodetachment of H− ion near two repulsive centers. Using the semiclassical closed orbit theory, we study the classical motion of the detached electron and calculate the photodetachment cross section of H− ion near two repulsive centers. It is found that the repulsive centers have significant effects on the photodetachment of H− ion. The photodetachment cross section of our system is strongly oscillatory compared to the photodetachment near one repulsive center. The calculation results suggest: if one repulsive center is kept fixed, with the decrease of the distance between two repulsive centers, the oscillating amplitude in the cross section becomes enlarged and the photodetachment cross section exhibits a multi-periodic oscillatory structure. In order to show the correspondence between the oscillation in the photodetachment cross section and the detached electron's classical closed orbits clearly, we make a Fourier transformation for the scaled photodetachment cross section of this system. Each peak in the Fourier transformed cross section corresponds to the scaled action of one closed orbit. We hope that our study will be useful in directing the future experimental research of the photodetachment processes of multiply charged anions.