0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 0 0.5 1 1.5 2 Photon energy (eV) Cross section (a.u.) 0 50 100 150 200 250 300 0 0.5 1 1.5 2 2.5 x/a$_{0}$ | F(x) |  (arb. units) two−center system triatomic system (a) (b) FIG. 5: (a) The orientation average photodetachment cross sections of the two-center system and the orientation average triatomic anion system. The parameter d = 100 a$_{0}$ . (b) The transformations defined in Eq.(18) for the above two cross sections. 15